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* ZSH: (zsh).                     The Z Shell Manual.
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File: zsh.info,  Node: Parameters Used by the Shell,  Prev: Parameters Set by the Shell,  Up: Parameters

15.7 Parameters Used by the Shell
=================================

The following parameters are used by the shell.  Again, '<S>' indicates
that the parameter is special and '<Z>' indicates that the parameter
does not exist when the shell initializes in sh or ksh emulation mode.

In cases where there are two parameters with an upper- and lowercase
form of the same name, such as path and PATH, the lowercase form is an
array and the uppercase form is a scalar with the elements of the array
joined together by colons.  These are similar to tied parameters created
via 'typeset -T'.  The normal use for the colon-separated form is for
exporting to the environment, while the array form is easier to
manipulate within the shell.  Note that unsetting either of the pair
will unset the other; they retain their special properties when
recreated, and recreating one of the pair will recreate the other.

ARGV0
     If exported, its value is used as the argv[0] of external commands.
     Usually used in constructs like 'ARGV0=emacs nethack'.

BAUD
     The rate in bits per second at which data reaches the terminal.
     The line editor will use this value in order to compensate for a
     slow terminal by delaying updates to the display until necessary.
     If the parameter is unset or the value is zero the compensation
     mechanism is turned off.  The parameter is not set by default.

     This parameter may be profitably set in some circumstances, e.g.
     for slow modems dialing into a communications server, or on a slow
     wide area network.  It should be set to the baud rate of the
     slowest part of the link for best performance.

cdpath <S> <Z> (CDPATH <S>)
     An array (colon-separated list) of directories specifying the
     search path for the cd command.

COLUMNS <S>
     The number of columns for this terminal session.  Used for printing
     select lists and for the line editor.

CORRECT_IGNORE
     If set, is treated as a pattern during spelling correction.  Any
     potential correction that matches the pattern is ignored.  For
     example, if the value is '_*' then completion functions (which, by
     convention, have names beginning with '_') will never be offered as
     spelling corrections.  The pattern does not apply to the correction
     of file names, as applied by the CORRECT_ALL option (so with the
     example just given files beginning with '_' in the current
     directory would still be completed).

CORRECT_IGNORE_FILE
     If set, is treated as a pattern during spelling correction of file
     names.  Any file name that matches the pattern is never offered as
     a correction.  For example, if the value is '.*' then dot file
     names will never be offered as spelling corrections.  This is
     useful with the CORRECT_ALL option.

DIRSTACKSIZE
     The maximum size of the directory stack, by default there is no
     limit.  If the stack gets larger than this, it will be truncated
     automatically.  This is useful with the AUTO_PUSHD option.

ENV
     If the ENV environment variable is set when zsh is invoked as sh or
     ksh, $ENV is sourced after the profile scripts.  The value of ENV
     is subjected to parameter expansion, command substitution, and
     arithmetic expansion before being interpreted as a pathname.  Note
     that ENV is _not_ used unless the shell is interactive and zsh is
     emulating ‘sh’ or ‘ksh’.

FCEDIT
     The default editor for the fc builtin.  If FCEDIT is not set, the
     parameter EDITOR is used; if that is not set either, a builtin
     default, usually vi, is used.

fignore <S> <Z> (FIGNORE <S>)
     An array (colon separated list) containing the suffixes of files to
     be ignored during filename completion.  However, if completion only
     generates files with suffixes in this list, then these files are
     completed anyway.

fpath <S> <Z> (FPATH <S>)
     An array (colon separated list) of directories specifying the
     search path for function definitions.  This path is searched when a
     function with the -u attribute is referenced.  If an executable
     file is found, then it is read and executed in the current
     environment.

histchars <S>
     Three characters used by the shell's history and lexical analysis
     mechanism.  The first character signals the start of a history
     expansion (default '!').  The second character signals the start of
     a quick history substitution (default '^').  The third character is
     the comment character (default '#').

     The characters must be in the ASCII character set; any attempt to
     set histchars to characters with a locale-dependent meaning will be
     rejected with an error message.

HISTCHARS <S> <Z>
     Same as histchars.  (Deprecated.)

HISTFILE
     The file to save the history in when an interactive shell exits.
     If unset, the history is not saved.

HISTORY_IGNORE
     If set, is treated as a pattern at the time history files are
     written.  Any potential history entry that matches the pattern is
     skipped.  For example, if the value is 'fc *' then commands that
     invoke the interactive history editor are never written to the
     history file.

     Note that HISTORY_IGNORE defines a single pattern: to specify
     alternatives use the '(FIRST|SECOND|...)' syntax.

     Compare the HIST_NO_STORE option or the zshaddhistory hook, either
     of which would prevent such commands from being added to the
     interactive history at all.  If you wish to use HISTORY_IGNORE to
     stop history being added in the first place, you can define the
     following hook:

          zshaddhistory() {
            emulate -L zsh
            ## uncomment if HISTORY_IGNORE
            ## should use EXTENDED_GLOB syntax
            # setopt extendedglob
            [[ $1 != ${~HISTORY_IGNORE} ]]
          }

HISTSIZE <S>
     The maximum number of events stored in the internal history list.
     If you use the HIST_EXPIRE_DUPS_FIRST option, setting this value
     larger than the SAVEHIST size will give you the difference as a
     cushion for saving duplicated history events.

     If this is made local, it is not implicitly set to 0, but may be
     explicitly set locally.

HOME <S>
     The default argument for the cd command.  This is not set
     automatically by the shell in sh, ksh or csh emulation, but it is
     typically present in the environment anyway, and if it becomes set
     it has its usual special behaviour.

IFS <S>
     Internal field separators (by default space, tab, newline and NUL),
     that are used to separate words which result from command or
     parameter expansion and words read by the read builtin.  Any
     characters from the set space, tab and newline that appear in the
     IFS are called _IFS white space_.  One or more IFS white space
     characters or one non-IFS white space character together with any
     adjacent IFS white space character delimit a field.  If an IFS
     white space character appears twice consecutively in the IFS, this
     character is treated as if it were not an IFS white space
     character.

     If the parameter is unset, the default is used.  Note this has a
     different effect from setting the parameter to an empty string.

     If MULTIBYTE option is on and IFS contains invalid characters in
     the current locale, it is reset to the default.

KEYBOARD_HACK
     This variable defines a character to be removed from the end of the
     command line before interpreting it (interactive shells only).  It
     is intended to fix the problem with keys placed annoyingly close to
     return and replaces the SUNKEYBOARDHACK option which did this for
     backquotes only.  Should the chosen character be one of
     singlequote, doublequote or backquote, there must also be an odd
     number of them on the command line for the last one to be removed.

     For backward compatibility, if the SUNKEYBOARDHACK option is
     explicitly set, the value of KEYBOARD_HACK reverts to backquote.
     If the option is explicitly unset, this variable is set to empty.

KEYTIMEOUT
     The time the shell waits, in hundredths of seconds, for another key
     to be pressed when reading bound multi-character sequences.

LANG <S>
     This variable determines the locale category for any category not
     specifically selected via a variable starting with 'LC_'.

LC_ALL <S>
     This variable overrides the value of the 'LANG' variable and the
     value of any of the other variables starting with 'LC_'.

LC_COLLATE <S>
     This variable determines the locale category for character
     collation information within ranges in glob brackets and for
     sorting.

LC_CTYPE <S>
     This variable determines the locale category for character handling
     functions.  If the MULTIBYTE option is in effect this variable or
     LANG should contain a value that reflects the character set in use,
     even if it is a single-byte character set, unless only the 7-bit
     subset (ASCII) is used.  For example, if the character set is
     ISO-8859-1, a suitable value might be en_US.iso88591 (certain Linux
     distributions) or en_US.ISO8859-1 (MacOS).

LC_MESSAGES <S>
     This variable determines the language in which messages should be
     written.  Note that zsh does not use message catalogs.

LC_NUMERIC <S>
     This variable affects the decimal point character and thousands
     separator character for the formatted input/output functions and
     string conversion functions.  Note that zsh ignores this setting
     when parsing floating point mathematical expressions.

LC_TIME <S>
     This variable determines the locale category for date and time
     formatting in prompt escape sequences.

LINES <S>
     The number of lines for this terminal session.  Used for printing
     select lists and for the line editor.

LISTMAX
     In the line editor, the number of matches to list without asking
     first.  If the value is negative, the list will be shown if it
     spans at most as many lines as given by the absolute value.  If set
     to zero, the shell asks only if the top of the listing would scroll
     off the screen.

MAIL
     If this parameter is set and mailpath is not set, the shell looks
     for mail in the specified file.

MAILCHECK
     The interval in seconds between checks for new mail.

mailpath <S> <Z> (MAILPATH <S>)
     An array (colon-separated list) of filenames to check for new mail.
     Each filename can be followed by a '?' and a message that will be
     printed.  The message will undergo parameter expansion, command
     substitution and arithmetic expansion with the variable $_ defined
     as the name of the file that has changed.  The default message is
     'You have new mail'.  If an element is a directory instead of a
     file the shell will recursively check every file in every
     subdirectory of the element.

manpath <S> <Z> (MANPATH <S> <Z>)
     An array (colon-separated list) whose value is not used by the
     shell.  The manpath array can be useful, however, since setting it
     also sets MANPATH, and vice versa.

match
mbegin
mend
     Arrays set by the shell when the b globbing flag is used in pattern
     matches.  See *note Globbing Flags::.

MATCH
MBEGIN
MEND
     Set by the shell when the m globbing flag is used in pattern
     matches.  See *note Globbing Flags::.

module_path <S> <Z> (MODULE_PATH <S>)
     An array (colon-separated list) of directories that zmodload
     searches for dynamically loadable modules.  This is initialized to
     a standard pathname, usually '/usr/local/lib/zsh/$ZSH_VERSION'.
     (The '/usr/local/lib' part varies from installation to
     installation.)  For security reasons, any value set in the
     environment when the shell is started will be ignored.

     These parameters only exist if the installation supports dynamic
     module loading.

NULLCMD <S>
     The command name to assume if a redirection is specified with no
     command.  Defaults to cat.  For ‘sh’/‘ksh’ behavior, change this to
     :.  For ‘csh’-like behavior, unset this parameter; the shell will
     print an error message if null commands are entered.

path <S> <Z> (PATH <S>)
     An array (colon-separated list) of directories to search for
     commands.  When this parameter is set, each directory is scanned
     and all files found are put in a hash table.  Directories named by
     relative path are not scanned for hashing.

POSTEDIT <S>
     This string is output whenever the line editor exits.  It usually
     contains termcap strings to reset the terminal.

PROMPT <S> <Z>
PROMPT2 <S> <Z>
PROMPT3 <S> <Z>
PROMPT4 <S> <Z>
     Same as PS1, PS2, PS3 and PS4, respectively.

prompt <S> <Z>
     Same as PS1.

PROMPT_EOL_MARK
     When the PROMPT_CR and PROMPT_SP options are set, the
     PROMPT_EOL_MARK parameter can be used to customize how the end of
     partial lines are shown.  This parameter undergoes prompt
     expansion, with the PROMPT_PERCENT option set.  If not set, the
     default behavior is equivalent to the value '%B%S%#%s%b'.

PS1 <S>
     The primary prompt string, printed before a command is read.  It
     undergoes a special form of expansion before being displayed; see
     *note Expansion of Prompt Sequences::.  The default is '%m%# '.

PS2 <S>
     The secondary prompt, printed when the shell needs more information
     to complete a command.  It is expanded in the same way as PS1.  The
     default is '%_> ', which displays any shell constructs or quotation
     marks which are currently being processed.

PS3 <S>
     Selection prompt used within a select loop.  It is expanded in the
     same way as PS1.  The default is '?# '.

PS4 <S>
     The execution trace prompt.  Default is '+%N:%i> ', which displays
     the name of the current shell structure and the line number within
     it.  In sh or ksh emulation, the default is '+ '.

psvar <S> <Z> (PSVAR <S>)
     An array (colon-separated list) whose elements can be used in
     PROMPT strings.  Setting psvar also sets PSVAR, and vice versa.

READNULLCMD <S>
     The command name to assume if a single input redirection is
     specified with no command.  Defaults to more.

REPORTMEMORY
     If nonnegative, commands whose maximum resident set size (roughly
     speaking, main memory usage) in kilobytes is greater than this
     value have timing statistics reported.  The format used to output
     statistics is the value of the TIMEFMT parameter, which is the same
     as for the REPORTTIME variable and the time builtin; note that by
     default this does not output memory usage.  Appending " max RSS %M"
     to the value of TIMEFMT causes it to output the value that
     triggered the report.  If REPORTTIME is also in use, at most a
     single report is printed for both triggers.  This feature requires
     the getrusage() system call, commonly supported by modern Unix-like
     systems.

REPORTTIME
     If nonnegative, commands whose combined user and system execution
     times (measured in seconds) are greater than this value have timing
     statistics printed for them.  Output is suppressed for commands
     executed within the line editor, including completion; commands
     explicitly marked with the time keyword still cause the summary to
     be printed in this case.

REPLY
     This parameter is reserved by convention to pass string values
     between shell scripts and shell builtins in situations where a
     function call or redirection are impossible or undesirable.  The
     read builtin and the select complex command may set REPLY, and
     filename generation both sets and examines its value when
     evaluating certain expressions.  Some modules also employ REPLY for
     similar purposes.

reply
     As REPLY, but for array values rather than strings.

RPROMPT <S>
RPS1 <S>
     This prompt is displayed on the right-hand side of the screen when
     the primary prompt is being displayed on the left.  This does not
     work if the SINGLE_LINE_ZLE option is set.  It is expanded in the
     same way as PS1.

RPROMPT2 <S>
RPS2 <S>
     This prompt is displayed on the right-hand side of the screen when
     the secondary prompt is being displayed on the left.  This does not
     work if the SINGLE_LINE_ZLE option is set.  It is expanded in the
     same way as PS2.

SAVEHIST
     The maximum number of history events to save in the history file.

     If this is made local, it is not implicitly set to 0, but may be
     explicitly set locally.

SPROMPT <S>
     The prompt used for spelling correction.  The sequence '%R' expands
     to the string which presumably needs spelling correction, and '%r'
     expands to the proposed correction.  All other prompt escapes are
     also allowed.

     The actions available at the prompt are [nyae]:
     n ('no') (default)
          Discard the correction.  If there are no more corrections,
          accept the command line, else (with CORRECT_ALL) prompt for
          the next.
     y ('yes')
          Make the correction.  If there are no more corrections, accept
          the command line.
     a ('abort')
          Place the entire command line in the history for later edit,
          but without accepting it.
     e ('edit')
          Resume editing the command line.

STTY
     If this parameter is set in a command's environment, the shell runs
     the stty command with the value of this parameter as arguments in
     order to set up the terminal before executing the command.  The
     modes apply only to the command, and are reset when it finishes or
     is suspended.  If the command is suspended and continued later with
     the fg or wait builtins it will see the modes specified by STTY, as
     if it were not suspended.  This (intentionally) does not apply if
     the command is continued via 'kill -CONT'.  STTY is ignored if the
     command is run in the background, or if it is in the environment of
     the shell but not explicitly assigned to in the input line.  This
     avoids running stty at every external command by accidentally
     exporting it.  Also note that STTY should not be used for window
     size specifications; these will not be local to the command.

     If the parameter is set and empty, all of the above applies except
     that stty is not run.  This can be useful as a way to freeze the
     tty around a single command, blocking its changes to tty settings,
     similar to the ttyctl builtin.

TERM <S>
     The type of terminal in use.  This is used when looking up termcap
     sequences.  An assignment to TERM causes zsh to re-initialize the
     terminal, even if the value does not change (e.g., 'TERM=$TERM').
     It is necessary to make such an assignment upon any change to the
     terminal definition database or terminal type in order for the new
     settings to take effect.

TERMINFO <S>
     A reference to your terminfo database, used by the 'terminfo'
     library when the system has it; see terminfo(5).  If set, this
     causes the shell to reinitialise the terminal, making the
     workaround 'TERM=$TERM' unnecessary.

TERMINFO_DIRS <S>
     A colon-seprarated list of terminfo databases, used by the
     'terminfo' library when the system has it; see terminfo(5).  This
     variable is only used by certain terminal libraries, in particular
     ncurses; see terminfo(5) to check support on your system.  If set,
     this causes the shell to reinitialise the terminal, making the
     workaround 'TERM=$TERM' unnecessary.  Note that unlike other
     colon-separated arrays this is not tied to a zsh array.

TIMEFMT
     The format of process time reports with the time keyword.  The
     default is '%J %U user %S system %P cpu %*E total'.  Recognizes the
     following escape sequences, although not all may be available on
     all systems, and some that are available may not be useful:

     %%
          A '%'.
     %U
          CPU seconds spent in user mode.
     %S
          CPU seconds spent in kernel mode.
     %E
          Elapsed time in seconds.
     %P
          The CPU percentage, computed as 100*(%U+%S)/%E.
     %W
          Number of times the process was swapped.
     %X
          The average amount in (shared) text space used in kilobytes.
     %D
          The average amount in (unshared) data/stack space used in
          kilobytes.
     %K
          The total space used (%X+%D) in kilobytes.
     %M
          The maximum memory the process had in use at any time in
          kilobytes.
     %F
          The number of major page faults (page needed to be brought
          from disk).
     %R
          The number of minor page faults.
     %I
          The number of input operations.
     %O
          The number of output operations.
     %r
          The number of socket messages received.
     %s
          The number of socket messages sent.
     %k
          The number of signals received.
     %w
          Number of voluntary context switches (waits).
     %c
          Number of involuntary context switches.
     %J
          The name of this job.

     A star may be inserted between the percent sign and flags printing
     time (e.g., '%*E'); this causes the time to be printed in
     'HH:MM:SS.TTT' format (hours and minutes are only printed if they
     are not zero).  Alternatively, 'm', 'u', or 'n' may be used (e.g.,
     '%mE') to produce time output in milliseconds, microseconds, or
     nanoseconds, respectively.  Note that some timings on some
     platforms are not actually nanosecond-precise (nor accurate to 1 ns
     when they are); in fact on many systems user and kernel times are
     not even microsecond-precise.

TMOUT
     If this parameter is nonzero, the shell will receive an ALRM signal
     if a command is not entered within the specified number of seconds
     after issuing a prompt.  If there is a trap on SIGALRM, it will be
     executed and a new alarm is scheduled using the value of the TMOUT
     parameter after executing the trap.  If no trap is set, and the
     idle time of the terminal is not less than the value of the TMOUT
     parameter, zsh terminates.  Otherwise a new alarm is scheduled to
     TMOUT seconds after the last keypress.

TMPPREFIX
     A pathname prefix which the shell will use for all temporary files.
     Note that this should include an initial part for the file name as
     well as any directory names.  The default is '/tmp/zsh'.

TMPSUFFIX
     A filename suffix which the shell will use for temporary files
     created by process substitutions (e.g., '=(LIST)').  Note that the
     value should include a leading dot '.' if intended to be
     interpreted as a file extension.  The default is not to append any
     suffix, thus this parameter should be assigned only when needed and
     then unset again.

WORDCHARS <S>
     A list of non-alphanumeric characters considered part of a word by
     the line editor.

ZBEEP
     If set, this gives a string of characters, which can use all the
     same codes as the bindkey command as described in *note The zsh/zle
     Module::, that will be output to the terminal instead of beeping.
     This may have a visible instead of an audible effect; for example,
     the string '\e[?5h\e[?5l' on a vt100 or xterm will have the effect
     of flashing reverse video on and off (if you usually use reverse
     video, you should use the string '\e[?5l\e[?5h' instead).  This
     takes precedence over the NOBEEP option.

ZDOTDIR
     The directory to search for shell startup files (.zshrc, etc), if
     not $HOME.

zle_bracketed_paste
     Many terminal emulators have a feature that allows applications to
     identify when text is pasted into the terminal rather than being
     typed normally.  For ZLE, this means that special characters such
     as tabs and newlines can be inserted instead of invoking editor
     commands.  Furthermore, pasted text forms a single undo event and
     if the region is active, pasted text will replace the region.

     This two-element array contains the terminal escape sequences for
     enabling and disabling the feature.  These escape sequences are
     used to enable bracketed paste when ZLE is active and disable it at
     other times.  Unsetting the parameter has the effect of ensuring
     that bracketed paste remains disabled.

zle_highlight
     An array describing contexts in which ZLE should highlight the
     input text.  See *note Character Highlighting::.

ZLE_LINE_ABORTED
     This parameter is set by the line editor when an error occurs.  It
     contains the line that was being edited at the point of the error.
     'print -zr -- $ZLE_LINE_ABORTED' can be used to recover the line.
     Only the most recent line of this kind is remembered.

ZLE_REMOVE_SUFFIX_CHARS
ZLE_SPACE_SUFFIX_CHARS
     These parameters are used by the line editor.  In certain
     circumstances suffixes (typically space or slash) added by the
     completion system will be removed automatically, either because the
     next editing command was not an insertable character, or because
     the character was marked as requiring the suffix to be removed.

     These variables can contain the sets of characters that will cause
     the suffix to be removed.  If ZLE_REMOVE_SUFFIX_CHARS is set, those
     characters will cause the suffix to be removed; if
     ZLE_SPACE_SUFFIX_CHARS is set, those characters will cause the
     suffix to be removed and replaced by a space.

     If ZLE_REMOVE_SUFFIX_CHARS is not set, the default behaviour is
     equivalent to:

          ZLE_REMOVE_SUFFIX_CHARS=$' \t\n;&|'

     If ZLE_REMOVE_SUFFIX_CHARS is set but is empty, no characters have
     this behaviour.  ZLE_SPACE_SUFFIX_CHARS takes precedence, so that
     the following:

          ZLE_SPACE_SUFFIX_CHARS=$'&|'

     causes the characters '&' and '|' to remove the suffix but to
     replace it with a space.

     To illustrate the difference, suppose that the option
     AUTO_REMOVE_SLASH is in effect and the directory DIR has just been
     completed, with an appended /, following which the user types '&'.
     The default result is 'DIR&'.  With ZLE_REMOVE_SUFFIX_CHARS set but
     without including '&' the result is 'DIR/&'.  With
     ZLE_SPACE_SUFFIX_CHARS set to include '&' the result is 'DIR &'.

     Note that certain completions may provide their own suffix removal
     or replacement behaviour which overrides the values described here.
     See the completion system documentation in *note Completion
     System::.

ZLE_RPROMPT_INDENT <S>
     If set, used to give the indentation between the right hand side of
     the right prompt in the line editor as given by RPS1 or RPROMPT and
     the right hand side of the screen.  If not set, the value 1 is
     used.

     Typically this will be used to set the value to 0 so that the
     prompt appears flush with the right hand side of the screen.  This
     is not the default as many terminals do not handle this correctly,
     in particular when the prompt appears at the extreme bottom right
     of the screen.  Recent virtual terminals are more likely to handle
     this case correctly.  Some experimentation is necessary.


File: zsh.info,  Node: Options,  Next: Shell Builtin Commands,  Prev: Parameters,  Up: Top

16 Options
**********

* Menu:

* Specifying Options::
* Description of Options::
* Option Aliases::
* Single Letter Options::


File: zsh.info,  Node: Specifying Options,  Next: Description of Options,  Up: Options

16.1 Specifying Options
=======================

Options are primarily referred to by name.  These names are case
insensitive and underscores are ignored.  For example, 'allexport' is
equivalent to 'A__lleXP_ort'.

The sense of an option name may be inverted by preceding it with 'no',
so 'setopt No_Beep' is equivalent to 'unsetopt beep'.  This inversion
can only be done once, so 'nonobeep' is _not_ a synonym for 'beep'.
Similarly, 'tify' is not a synonym for 'nonotify' (the inversion of
'notify').

Some options also have one or more single letter names.  There are two
sets of single letter options: one used by default, and another used to
emulate ‘sh’/‘ksh’ (used when the SH_OPTION_LETTERS option is set).  The
single letter options can be used on the shell command line, or with the
set, setopt and unsetopt builtins, as normal Unix options preceded by
'-'.

The sense of the single letter options may be inverted by using '+'
instead of '-'.  Some of the single letter option names refer to an
option being off, in which case the inversion of that name refers to the
option being on.  For example, '+n' is the short name of 'exec', and
'-n' is the short name of its inversion, 'noexec'.

In strings of single letter options supplied to the shell at startup,
trailing whitespace will be ignored; for example the string '-f ' will
be treated just as '-f', but the string '-f i' is an error.  This is
because many systems which implement the '#!' mechanism for calling
scripts do not strip trailing whitespace.

It is possible for options to be set within a function scope.  See the
description of the option LOCAL_OPTIONS below.


File: zsh.info,  Node: Description of Options,  Next: Option Aliases,  Prev: Specifying Options,  Up: Options

16.2 Description of Options
===========================

In the following list, options set by default in all emulations are
marked <D>; those set by default only in csh, ksh, sh, or zsh emulations
are marked <C>, <K>, <S>, <Z> as appropriate.  When listing options (by
'setopt', 'unsetopt', 'set -o' or 'set +o'), those turned on by default
appear in the list prefixed with 'no'.  Hence (unless KSH_OPTION_PRINT
is set), 'setopt' shows all options whose settings are changed from the
default.

16.2.1 Changing Directories
---------------------------

AUTO_CD (-J)
     If a command is issued that can't be executed as a normal command,
     and the command is the name of a directory, perform the cd command
     to that directory.  This option is only applicable if the option
     SHIN_STDIN is set, i.e.  if commands are being read from standard
     input.  The option is designed for interactive use; it is
     recommended that cd be used explicitly in scripts to avoid
     ambiguity.

AUTO_PUSHD (-N)
     Make cd push the old directory onto the directory stack.

CDABLE_VARS (-T)
     If the argument to a cd command (or an implied cd with the AUTO_CD
     option set) is not a directory, and does not begin with a slash,
     try to expand the expression as if it were preceded by a '~' (see
     *note Filename Expansion::).

CD_SILENT
     Never print the working directory after a cd (whether explicit or
     implied with the AUTO_CD option set).  cd normally prints the
     working directory when the argument given to it was -, a stack
     entry, or the name of a directory found under CDPATH.  Note that
     this is distinct from pushd's stack-printing behaviour, which is
     controlled by PUSHD_SILENT.  This option overrides the
     printing-related effects of POSIX_CD.

CHASE_DOTS
     When changing to a directory containing a path segment '..' which
     would otherwise be treated as canceling the previous segment in the
     path (in other words, 'foo/..' would be removed from the path, or
     if '..' is the first part of the path, the last part of the current
     working directory would be removed), instead resolve the path to
     the physical directory.  This option is overridden by CHASE_LINKS.

     For example, suppose /foo/bar is a link to the directory /alt/rod.
     Without this option set, 'cd /foo/bar/..' changes to /foo; with it
     set, it changes to /alt.  The same applies if the current directory
     is /foo/bar and 'cd ..' is used.  Note that all other symbolic
     links in the path will also be resolved.

CHASE_LINKS (-w)
     Resolve symbolic links to their true values when changing
     directory.  This also has the effect of CHASE_DOTS, i.e.  a '..'
     path segment will be treated as referring to the physical parent,
     even if the preceding path segment is a symbolic link.

POSIX_CD <K> <S>
     Modifies the behaviour of cd, chdir and pushd commands to make them
     more compatible with the POSIX standard.  The behaviour with the
     option unset is described in the documentation for the cd builtin
     in *note Shell Builtin Commands::.  If the option is set, the shell
     does not test for directories beneath the local directory ('.')
     until after all directories in cdpath have been tested, and the cd
     and chdir commands do not recognise arguments of the form '{+|-}N'
     as directory stack entries.

     Also, if the option is set, the conditions under which the shell
     prints the new directory after changing to it are modified.  It is
     no longer restricted to interactive shells (although printing of
     the directory stack with pushd is still limited to interactive
     shells); and any use of a component of CDPATH, including a '.' but
     excluding an empty component that is otherwise treated as '.',
     causes the directory to be printed.

PUSHD_IGNORE_DUPS
     Don't push multiple copies of the same directory onto the directory
     stack.

PUSHD_MINUS
     Exchanges the meanings of '+' and '-' when used with a number to
     specify a directory in the stack.

PUSHD_SILENT (-E)
     Do not print the directory stack after pushd or popd.

PUSHD_TO_HOME (-D)
     Have pushd with no arguments act like 'pushd $HOME'.

16.2.2 Completion
-----------------

ALWAYS_LAST_PROMPT <D>
     If unset, key functions that list completions try to return to the
     last prompt if given a numeric argument.  If set these functions
     try to return to the last prompt if given _no_ numeric argument.

ALWAYS_TO_END
     If a completion is performed with the cursor within a word, and a
     full completion is inserted, the cursor is moved to the end of the
     word.  That is, the cursor is moved to the end of the word if
     either a single match is inserted or menu completion is performed.

AUTO_LIST (-9) <D>
     Automatically list choices on an ambiguous completion.

AUTO_MENU <D>
     Automatically use menu completion after the second consecutive
     request for completion, for example by pressing the tab key
     repeatedly.  This option is overridden by MENU_COMPLETE.

AUTO_NAME_DIRS
     Any parameter that is set to the absolute name of a directory
     immediately becomes a name for that directory, that will be used by
     the '%~' and related prompt sequences, and will be available when
     completion is performed on a word starting with '~'.  (Otherwise,
     the parameter must be used in the form '~PARAM' first.)

AUTO_PARAM_KEYS <D>
     If a parameter name was completed and a following character
     (normally a space) automatically inserted, and the next character
     typed is one of those that have to come directly after the name
     (like '}', ':', etc.), the automatically added character is
     deleted, so that the character typed comes immediately after the
     parameter name.  Completion in a brace expansion is affected
     similarly: the added character is a ',', which will be removed if
     '}' is typed next.

AUTO_PARAM_SLASH <D>
     If a parameter is completed whose content is the name of a
     directory, then add a trailing slash instead of a space.

AUTO_REMOVE_SLASH <D>
     When the last character resulting from a completion is a slash and
     the next character typed is a word delimiter, a slash, or a
     character that ends a command (such as a semicolon or an
     ampersand), remove the slash.

BASH_AUTO_LIST
     On an ambiguous completion, automatically list choices when the
     completion function is called twice in succession.  This takes
     precedence over AUTO_LIST.  The setting of LIST_AMBIGUOUS is
     respected.  If AUTO_MENU is set, the menu behaviour will then start
     with the third press.  Note that this will not work with
     MENU_COMPLETE, since repeated completion calls immediately cycle
     through the list in that case.

COMPLETE_ALIASES
     Prevents aliases on the command line from being internally
     substituted before completion is attempted.  The effect is to make
     the alias a distinct command for completion purposes.

COMPLETE_IN_WORD
     If unset, the cursor is set to the end of the word if completion is
     started.  Otherwise it stays there and completion is done from both
     ends.

GLOB_COMPLETE
     When the current word has a glob pattern, do not insert all the
     words resulting from the expansion but generate matches as for
     completion and cycle through them like MENU_COMPLETE.  The matches
     are generated as if a '*' was added to the end of the word, or
     inserted at the cursor when COMPLETE_IN_WORD is set.  This actually
     uses pattern matching, not globbing, so it works not only for files
     but for any completion, such as options, user names, etc.

     Note that when the pattern matcher is used, matching control (for
     example, case-insensitive or anchored matching) cannot be used.
     This limitation only applies when the current word contains a
     pattern; simply turning on the GLOB_COMPLETE option does not have
     this effect.

HASH_LIST_ALL <D>
     Whenever a command completion or spelling correction is attempted,
     make sure the entire command path is hashed first.  This makes the
     first completion slower but avoids false reports of spelling
     errors.

LIST_AMBIGUOUS <D>
     This option works when AUTO_LIST or BASH_AUTO_LIST is also set.  If
     there is an unambiguous prefix to insert on the command line, that
     is done without a completion list being displayed; in other words,
     auto-listing behaviour only takes place when nothing would be
     inserted.  In the case of BASH_AUTO_LIST, this means that the list
     will be delayed to the third call of the function.

LIST_BEEP <D>
     Beep on an ambiguous completion.  More accurately, this forces the
     completion widgets to return status 1 on an ambiguous completion,
     which causes the shell to beep if the option BEEP is also set; this
     may be modified if completion is called from a user-defined widget.

LIST_PACKED
     Try to make the completion list smaller (occupying less lines) by
     printing the matches in columns with different widths.

LIST_ROWS_FIRST
     Lay out the matches in completion lists sorted horizontally, that
     is, the second match is to the right of the first one, not under it
     as usual.

LIST_TYPES (-X) <D>
     When listing files that are possible completions, show the type of
     each file with a trailing identifying mark.

MENU_COMPLETE (-Y)
     On an ambiguous completion, instead of listing possibilities or
     beeping, insert the first match immediately.  Then when completion
     is requested again, remove the first match and insert the second
     match, etc.  When there are no more matches, go back to the first
     one again.  reverse-menu-complete may be used to loop through the
     list in the other direction.  This option overrides AUTO_MENU.

REC_EXACT (-S)
     If the string on the command line exactly matches one of the
     possible completions, it is accepted, even if there is another
     completion (i.e.  that string with something else added) that also
     matches.

16.2.3 Expansion and Globbing
-----------------------------

BAD_PATTERN (+2) <C> <Z>
     If a pattern for filename generation is badly formed, print an
     error message.  (If this option is unset, the pattern will be left
     unchanged.)

BARE_GLOB_QUAL <Z>
     In a glob pattern, treat a trailing set of parentheses as a
     qualifier list, if it contains no unquoted '|', '(' or (if special)
     '~' characters.  See *note Filename Generation::.

BRACE_CCL
     Expand expressions in braces which would not otherwise undergo
     brace expansion to a lexically ordered list of all the characters.
     See *note Brace Expansion::.

CASE_GLOB <D>
     Make globbing (filename generation) sensitive to case.  Note that
     other uses of patterns are always sensitive to case.  If the option
     is unset, the presence of any character which is special to
     filename generation will cause case-insensitive matching.  For
     example, cvs(/) can match the directory CVS owing to the presence
     of the globbing flag (unless the option BARE_GLOB_QUAL is unset).

CASE_MATCH <D>
     Make regular expressions using the zsh/regex module (including
     matches with =~) sensitive to case.

CASE_PATHS
     If CASE_PATHS is not set (the default), CASE_GLOB affects the
     interpretation of _every_ path component, whenever a special
     character appears in _any_ component.  When CASE_PATHS is set, file
     path components that do _not_ contain special filename generation
     characters are always sensitive to case, thus restricting
     NO_CASE_GLOB to components that contain globbing characters.

     Note that if the filesystem itself is not sensitive to case, then
     CASE_PATHS has no effect.

CSH_NULL_GLOB <C>
     If a pattern for filename generation has no matches, delete the
     pattern from the argument list; do not report an error unless all
     the patterns in a command have no matches.  Overrides NOMATCH.

EQUALS <Z>
     Perform = filename expansion.  (See *note Filename Expansion::.)

EXTENDED_GLOB
     Treat the '#', '~' and '^' characters as part of patterns for
     filename generation, etc.  (An initial unquoted '~' always produces
     named directory expansion.)

FORCE_FLOAT
     Constants in arithmetic evaluation will be treated as floating
     point even without the use of a decimal point; the values of
     integer variables will be converted to floating point when used in
     arithmetic expressions.  Integers in any base will be converted.

GLOB (+F, ksh: +f) <D>
     Perform filename generation (globbing).  (See *note Filename
     Generation::.)

GLOB_ASSIGN <C>
     If this option is set, filename generation (globbing) is performed
     on the right hand side of scalar parameter assignments of the form
     'NAME=PATTERN (e.g.  'foo=*').  If the result has more than one
     word the parameter will become an array with those words as
     arguments.  This option is provided for backwards compatibility
     only: globbing is always performed on the right hand side of array
     assignments of the form 'NAME=(VALUE)' (e.g.  'foo=(*)') and this
     form is recommended for clarity; with this option set, it is not
     possible to predict whether the result will be an array or a
     scalar.

GLOB_DOTS (-4)
     Do not require a leading '.' in a filename to be matched
     explicitly.

GLOB_STAR_SHORT
     When this option is set and the default zsh-style globbing is in
     effect, the pattern '**/*' can be abbreviated to '**' and the
     pattern '***/*' can be abbreviated to ***.  Hence '**.c' finds a
     file ending in .c in any subdirectory, and '***.c' does the same
     while also following symbolic links.  A / immediately after the
     '**' or '***' forces the pattern to be treated as the unabbreviated
     form.

GLOB_SUBST <C> <K> <S>
     Treat any characters resulting from parameter expansion as being
     eligible for filename expansion and filename generation, and any
     characters resulting from command substitution as being eligible
     for filename generation.  Braces (and commas in between) do not
     become eligible for expansion.

HIST_SUBST_PATTERN
     Substitutions using the :s and :& history modifiers are performed
     with pattern matching instead of string matching.  This occurs
     wherever history modifiers are valid, including glob qualifiers and
     parameters.  See *note Modifiers::.

IGNORE_BRACES (-I) <S>
     Do not perform brace expansion.  For historical reasons this also
     includes the effect of the IGNORE_CLOSE_BRACES option.

IGNORE_CLOSE_BRACES
     When neither this option nor IGNORE_BRACES is set, a sole close
     brace character '}' is syntactically significant at any point on a
     command line.  This has the effect that no semicolon or newline is
     necessary before the brace terminating a function or current shell
     construct.  When either option is set, a closing brace is
     syntactically significant only in command position.  Unlike
     IGNORE_BRACES, this option does not disable brace expansion.

     For example, with both options unset a function may be defined in
     the following fashion:

          args() { echo $# }

     while if either option is set, this does not work and something
     equivalent to the following is required:

          args() { echo $#; }

KSH_GLOB <K>
     In pattern matching, the interpretation of parentheses is affected
     by a preceding '@', '*', '+', '?' or '!'.  See *note Filename
     Generation::.

MAGIC_EQUAL_SUBST
     All unquoted arguments of the form 'ANYTHING=EXPRESSION' appearing
     after the command name have filename expansion (that is, where
     EXPRESSION has a leading '~' or '=') performed on EXPRESSION as if
     it were a parameter assignment.  The argument is not otherwise
     treated specially; it is passed to the command as a single
     argument, and not used as an actual parameter assignment.  For
     example, in echo foo=~/bar:~/rod, both occurrences of ~ would be
     replaced.  Note that this happens anyway with typeset and similar
     statements.

     This option respects the setting of the KSH_TYPESET option.  In
     other words, if both options are in effect, arguments looking like
     assignments will not undergo word splitting.

MARK_DIRS (-8, ksh: -X)
     Append a trailing '/' to all directory names resulting from
     filename generation (globbing).

MULTIBYTE <D>
     Respect multibyte characters when found in strings.  When this
     option is set, strings are examined using the system library to
     determine how many bytes form a character, depending on the current
     locale.  This affects the way characters are counted in pattern
     matching, parameter values and various delimiters.

     The option is on by default if the shell was compiled with
     MULTIBYTE_SUPPORT; otherwise it is off by default and has no effect
     if turned on.

     If the option is off a single byte is always treated as a single
     character.  This setting is designed purely for examining strings
     known to contain raw bytes or other values that may not be
     characters in the current locale.  It is not necessary to unset the
     option merely because the character set for the current locale does
     not contain multibyte characters.

     The option does not affect the shell's editor, which always uses
     the locale to determine multibyte characters.  This is because the
     character set displayed by the terminal emulator is independent of
     shell settings.

NOMATCH (+3) <C> <Z>
     If a pattern for filename generation has no matches, print an
     error, instead of leaving it unchanged in the argument list.  This
     also applies to file expansion of an initial '~' or '='.

NULL_GLOB (-G)
     If a pattern for filename generation has no matches, delete the
     pattern from the argument list instead of reporting an error.
     Overrides NOMATCH.

NUMERIC_GLOB_SORT
     If numeric filenames are matched by a filename generation pattern,
     sort the filenames numerically rather than lexicographically.

RC_EXPAND_PARAM (-P)
     Array expansions of the form 'FOO${XX}BAR', where the parameter XX
     is set to (A B C), are substituted with 'FOOABAR FOOBBAR FOOCBAR'
     instead of the default 'FOOA B CBAR'.  Note that an empty array
     will therefore cause all arguments to be removed.

REMATCH_PCRE
     If set, regular expression matching with the =~ operator will use
     Perl-Compatible Regular Expressions from the PCRE library.  (The
     zsh/pcre module must be available.)  If not set, regular
     expressions will use the extended regexp syntax provided by the
     system libraries.

SH_GLOB <K> <S>
     Disables the special meaning of '(', '|', ')' and '<' for globbing
     the result of parameter and command substitutions, and in some
     other places where the shell accepts patterns.  If SH_GLOB is set
     but KSH_GLOB is not, the shell allows the interpretation of
     subshell expressions enclosed in parentheses in some cases where
     there is no space before the opening parenthesis, e.g.  !(true) is
     interpreted as if there were a space after the !.  This option is
     set by default if zsh is invoked as sh or ksh.

UNSET (+u, ksh: +u) <K> <S> <Z>
     Treat unset parameters as if they were empty when substituting, and
     as if they were zero when reading their values in arithmetic
     expansion and arithmetic commands.  Otherwise they are treated as
     an error.

WARN_CREATE_GLOBAL
     Print a warning message when a global parameter is created in a
     function by an assignment or in math context.  This often indicates
     that a parameter has not been declared local when it should have
     been.  Parameters explicitly declared global from within a function
     using typeset -g do not cause a warning.  Note that there is no
     warning when a local parameter is assigned to in a nested function,
     which may also indicate an error.

WARN_NESTED_VAR
     Print a warning message when an existing parameter from an
     enclosing function scope, or global, is set in a function by an
     assignment or in math context.  Assignment to shell special
     parameters does not cause a warning.  This is the companion to
     WARN_CREATE_GLOBAL as in this case the warning is only printed when
     a parameter is _not_ created.  Where possible, use of typeset -g to
     set the parameter suppresses the error, but note that this needs to
     be used every time the parameter is set.  To restrict the effect of
     this option to a single function scope, use 'functions -W'.

     For example, the following code produces a warning for the
     assignment inside the function nested as that overrides the value
     within toplevel

          toplevel() {
            local foo="in fn"
            nested
          }
          nested() {
               foo="in nested"
          }
          setopt warn_nested_var
          toplevel

16.2.4 History
--------------

APPEND_HISTORY <D>
     If this is set, zsh sessions will append their history list to the
     history file, rather than replace it.  Thus, multiple parallel zsh
     sessions will all have the new entries from their history lists
     added to the history file, in the order that they exit.  The file
     will still be periodically re-written to trim it when the number of
     lines grows 20% beyond the value specified by $SAVEHIST (see also
     the HIST_SAVE_BY_COPY option).

BANG_HIST (+K) <C> <Z>
     Perform textual history expansion, ‘csh’-style, treating the
     character '!' specially.

EXTENDED_HISTORY <C>
     Save each command's beginning timestamp (in seconds since the
     epoch) and the duration (in seconds) to the history file.  The
     format of this prefixed data is:

     ': <BEGINNING TIME>:<ELAPSED SECONDS>;<COMMAND>'.

HIST_ALLOW_CLOBBER
     Add '|' to output redirections in the history.  This allows history
     references to clobber files even when CLOBBER is unset.

HIST_BEEP <D>
     Beep in ZLE when a widget attempts to access a history entry which
     isn't there.

HIST_EXPIRE_DUPS_FIRST
     If the internal history needs to be trimmed to add the current
     command line, setting this option will cause the oldest history
     event that has a duplicate to be lost before losing a unique event
     from the list.  You should be sure to set the value of HISTSIZE to
     a larger number than SAVEHIST in order to give you some room for
     the duplicated events, otherwise this option will behave just like
     HIST_IGNORE_ALL_DUPS once the history fills up with unique events.

HIST_FCNTL_LOCK
     When writing out the history file, by default zsh uses ad-hoc file
     locking to avoid known problems with locking on some operating
     systems.  With this option locking is done by means of the system's
     fcntl call, where this method is available.  On recent operating
     systems this may provide better performance, in particular avoiding
     history corruption when files are stored on NFS.

HIST_FIND_NO_DUPS
     When searching for history entries in the line editor, do not
     display duplicates of a line previously found, even if the
     duplicates are not contiguous.

HIST_IGNORE_ALL_DUPS
     If a new command line being added to the history list duplicates an
     older one, the older command is removed from the list (even if it
     is not the previous event).

HIST_IGNORE_DUPS (-h)
     Do not enter command lines into the history list if they are
     duplicates of the previous event.

HIST_IGNORE_SPACE (-g)
     Remove command lines from the history list when the first character
     on the line is a space, or when one of the expanded aliases
     contains a leading space.  Only normal aliases (not global or
     suffix aliases) have this behaviour.  Note that the command lingers
     in the internal history until the next command is entered before it
     vanishes, allowing you to briefly reuse or edit the line.  If you
     want to make it vanish right away without entering another command,
     type a space and press return.

HIST_LEX_WORDS
     By default, shell history that is read in from files is split into
     words on all white space.  This means that arguments with quoted
     whitespace are not correctly handled, with the consequence that
     references to words in history lines that have been read from a
     file may be inaccurate.  When this option is set, words read in
     from a history file are divided up in a similar fashion to normal
     shell command line handling.  Although this produces more
     accurately delimited words, if the size of the history file is
     large this can be slow.  Trial and error is necessary to decide.

HIST_NO_FUNCTIONS
     Remove function definitions from the history list.  Note that the
     function lingers in the internal history until the next command is
     entered before it vanishes, allowing you to briefly reuse or edit
     the definition.

HIST_NO_STORE
     Remove the history (fc -l) command from the history list when
     invoked.  Note that the command lingers in the internal history
     until the next command is entered before it vanishes, allowing you
     to briefly reuse or edit the line.

HIST_REDUCE_BLANKS
     Remove superfluous blanks from each command line being added to the
     history list.

HIST_SAVE_BY_COPY <D>
     When the history file is re-written, we normally write out a copy
     of the file named $HISTFILE.new and then rename it over the old
     one.  However, if this option is unset, we instead truncate the old
     history file and write out the new version in-place.  If one of the
     history-appending options is enabled, this option only has an
     effect when the enlarged history file needs to be re-written to
     trim it down to size.  Disable this only if you have special needs,
     as doing so makes it possible to lose history entries if zsh gets
     interrupted during the save.

     When writing out a copy of the history file, zsh preserves the old
     file's permissions and group information, but will refuse to write
     out a new file if it would change the history file's owner.

HIST_SAVE_NO_DUPS
     When writing out the history file, older commands that duplicate
     newer ones are omitted.

HIST_VERIFY
     Whenever the user enters a line with history expansion, don't
     execute the line directly; instead, perform history expansion and
     reload the line into the editing buffer.

INC_APPEND_HISTORY
     This option works like APPEND_HISTORY except that new history lines
     are added to the $HISTFILE incrementally (as soon as they are
     entered), rather than waiting until the shell exits.  The file will
     still be periodically re-written to trim it when the number of
     lines grows 20% beyond the value specified by $SAVEHIST (see also
     the HIST_SAVE_BY_COPY option).

INC_APPEND_HISTORY_TIME
     This option is a variant of INC_APPEND_HISTORY in which, where
     possible, the history entry is written out to the file after the
     command is finished, so that the time taken by the command is
     recorded correctly in the history file in EXTENDED_HISTORY format.
     This means that the history entry will not be available immediately
     from other instances of the shell that are using the same history
     file.

     This option is only useful if INC_APPEND_HISTORY and SHARE_HISTORY
     are turned off.  The three options should be considered mutually
     exclusive.

SHARE_HISTORY <K>

     This option both imports new commands from the history file, and
     also causes your typed commands to be appended to the history file
     (the latter is like specifying INC_APPEND_HISTORY, which should be
     turned off if this option is in effect).  The history lines are
     also output with timestamps ala EXTENDED_HISTORY (which makes it
     easier to find the spot where we left off reading the file after it
     gets re-written).

     By default, history movement commands visit the imported lines as
     well as the local lines, but you can toggle this on and off with
     the set-local-history zle binding.  It is also possible to create a
     zle widget that will make some commands ignore imported commands,
     and some include them.

     If you find that you want more control over when commands get
     imported, you may wish to turn SHARE_HISTORY off,
     INC_APPEND_HISTORY or INC_APPEND_HISTORY_TIME (see above) on, and
     then manually import commands whenever you need them using 'fc
     -RI'.

16.2.5 Initialisation
---------------------

ALL_EXPORT (-a, ksh: -a)
     All parameters subsequently defined are automatically exported.

GLOBAL_EXPORT <Z>
     If this option is set, passing the -x flag to the builtins declare,
     float, integer, readonly and typeset (but not local) will also set
     the -g flag; hence parameters exported to the environment will not
     be made local to the enclosing function, unless they were already
     or the flag +g is given explicitly.  If the option is unset,
     exported parameters will be made local in just the same way as any
     other parameter.

     This option is set by default for backward compatibility; it is not
     recommended that its behaviour be relied upon.  Note that the
     builtin export always sets both the -x and -g flags, and hence its
     effect extends beyond the scope of the enclosing function; this is
     the most portable way to achieve this behaviour.

GLOBAL_RCS (+d) <D>
     If this option is unset, the startup files /etc/zprofile,
     /etc/zshrc, /etc/zlogin and /etc/zlogout will not be run.  It can
     be disabled and re-enabled at any time, including inside local
     startup files (.zshrc, etc.).

RCS (+f) <D>
     After /etc/zshenv is sourced on startup, source the .zshenv,
     /etc/zprofile, .zprofile, /etc/zshrc, .zshrc, /etc/zlogin, .zlogin,
     and .zlogout files, as described in *note Startup/Shutdown Files::.
     If this option is unset, the /etc/zshenv file is still sourced, but
     any of the others will not be; it can be set at any time to prevent
     the remaining startup files after the currently executing one from
     being sourced.

16.2.6 Input/Output
-------------------

ALIASES <D>
     Expand aliases.

CLOBBER (+C, ksh: +C) <D>
     Allows '>' redirection to truncate existing files.  Otherwise '>!'
     or '>|' must be used to truncate a file.

     If the option is not set, and the option APPEND_CREATE is also not
     set, '>>!' or '>>|' must be used to create a file.  If either
     option is set, '>>' may be used.

CLOBBER_EMPTY
     This option is only used if the option CLOBBER is not set: note
     that it is set by default.

     If this option is set, then regular files of zero length may be
     ovewritten ('clobbered').  Note that it is possible another process
     has written to the file between this test and use of the file by
     the current process.  This option should therefore not be used in
     cases where files to be clobbered may be written to asynchronously.

CORRECT (-0)
     Try to correct the spelling of commands.  Note that, when the
     HASH_LIST_ALL option is not set or when some directories in the
     path are not readable, this may falsely report spelling errors the
     first time some commands are used.

     Refer to the shell variable SPROMPT for an explanation of the
     '[nyae]' (no/yes/abort/edit) prompt that is offered.

     The shell variable CORRECT_IGNORE may be set to a pattern to match
     words that will never be offered as corrections.

CORRECT_ALL (-O)
     Try to correct the spelling of all arguments in a line, in order
     from left to right, treating each as a file name.  Answering 'a' or
     'e' at any prompt stops all corrections, otherwise every correction
     is prompted for.

     The shell variable CORRECT_IGNORE_FILE may be set to a pattern to
     match file names that will never be offered as corrections.

DVORAK
     Use the Dvorak keyboard instead of the standard qwerty keyboard as
     a basis for examining spelling mistakes for the CORRECT and
     CORRECT_ALL options and the spell-word editor command.

FLOW_CONTROL <D>
     If this option is unset, output flow control via start/stop
     characters (usually assigned to ^S/^Q) is disabled in the shell's
     editor.

IGNORE_EOF (-7)
     Do not exit on end-of-file.  Require the use of exit or logout
     instead.  However, ten consecutive EOFs will cause the shell to
     exit anyway, to avoid the shell hanging if its tty goes away.

     Also, if this option is set and the Zsh Line Editor is used,
     widgets implemented by shell functions can be bound to EOF
     (normally Control-D) without printing the normal warning message.
     This works only for normal widgets, not for completion widgets.

INTERACTIVE_COMMENTS (-k) <K> <S>
     Allow comments even in interactive shells.

HASH_CMDS <D>
     Note the location of each command the first time it is executed.
     Subsequent invocations of the same command will use the saved
     location, avoiding a path search.  If this option is unset, no path
     hashing is done at all.  However, when CORRECT is set, commands
     whose names do not appear in the functions or aliases hash tables
     are hashed in order to avoid reporting them as spelling errors.

HASH_DIRS <D>
     Whenever a command name is hashed, hash the directory containing
     it, as well as all directories that occur earlier in the path.  Has
     no effect if neither HASH_CMDS nor CORRECT is set.

HASH_EXECUTABLES_ONLY
     When hashing commands because of HASH_CMDS, check that the file to
     be hashed is actually an executable.  This option is unset by
     default as if the path contains a large number of commands, or
     consists of many remote files, the additional tests can take a long
     time.  Trial and error is needed to show if this option is
     beneficial.

MAIL_WARNING (-U)
     Print a warning message if a mail file has been accessed since the
     shell last checked.

PATH_DIRS (-Q)
     Perform a path search even on command names with slashes in them.
     Thus if '/usr/local/bin' is in the user's path, and he or she types
     'X11/xinit', the command '/usr/local/bin/X11/xinit' will be
     executed (assuming it exists).  Commands explicitly beginning with
     '/', './' or '../' are not subject to the path search.  This also
     applies to the '.' and source builtins.

     Note that subdirectories of the current directory are always
     searched for executables specified in this form.  This takes place
     before any search indicated by this option, and regardless of
     whether '.' or the current directory appear in the command search
     path.

PATH_SCRIPT <K> <S>
     If this option is not set, a script passed as the first non-option
     argument to the shell must contain the name of the file to open.
     If this option is set, and the script does not specify a directory
     path, the script is looked for first in the current directory, then
     in the command path.  See *note Invocation::.

PRINT_EIGHT_BIT
     Print eight bit characters literally in completion lists, etc.
     This option is not necessary if your system correctly returns the
     printability of eight bit characters (see ctype(3)).

PRINT_EXIT_VALUE (-1)
     Print the exit value of programs with non-zero exit status.  This
     is only available at the command line in interactive shells.

RC_QUOTES
     Allow the character sequence '''' to signify a single quote within
     singly quoted strings.  Note this does not apply in quoted strings
     using the format $'...', where a backslashed single quote can be
     used.

RM_STAR_SILENT (-H) <K> <S>
     Do not query the user before executing 'rm *' or 'rm path/*'.

RM_STAR_WAIT
     If querying the user before executing 'rm *' or 'rm path/*', first
     wait ten seconds and ignore anything typed in that time.  This
     avoids the problem of reflexively answering 'yes' to the query when
     one didn't really mean it.  The wait and query can always be
     avoided by expanding the '*' in ZLE (with tab).

SHORT_LOOPS <C> <Z>
     Allow the short forms of for, repeat, select, if, and function
     constructs.

SHORT_REPEAT
     Allow the short form repeat as SHORT_LOOPS but without enabling it
     for the other constructs.

SUN_KEYBOARD_HACK (-L)
     If a line ends with a backquote, and there are an odd number of
     backquotes on the line, ignore the trailing backquote.  This is
     useful on some keyboards where the return key is too small, and the
     backquote key lies annoyingly close to it.  As an alternative the
     variable KEYBOARD_HACK lets you choose the character to be removed.

16.2.7 Job Control
------------------

AUTO_CONTINUE
     With this option set, stopped jobs that are removed from the job
     table with the disown builtin command are automatically sent a CONT
     signal to make them running.

AUTO_RESUME (-W)
     Treat single word simple commands without redirection as candidates
     for resumption of an existing job.

BG_NICE (-6) <C> <Z>
     Run all background jobs at a lower priority.  This option is set by
     default.

CHECK_JOBS <Z>
     Report the status of background and suspended jobs before exiting a
     shell with job control; a second attempt to exit the shell will
     succeed.  NO_CHECK_JOBS is best used only in combination with
     NO_HUP, else such jobs will be killed automatically.

     The check is omitted if the commands run from the previous command
     line included a 'jobs' command, since it is assumed the user is
     aware that there are background or suspended jobs.  A 'jobs'
     command run from one of the hook functions defined in *note Special
     Functions:: is not counted for this purpose.

CHECK_RUNNING_JOBS <Z>
     Check for both running and suspended jobs when CHECK_JOBS is
     enabled.  When this option is disabled, zsh checks only for
     suspended jobs, which matches the default behavior of bash.

     This option has no effect unless CHECK_JOBS is set.

HUP <Z>
     Send the HUP signal to running jobs when the shell exits.

LONG_LIST_JOBS (-R)
     Print job notifications in the long format by default.

MONITOR (-m, ksh: -m)
     Allow job control.  Set by default in interactive shells.

NOTIFY (-5, ksh: -b) <Z>
     Report the status of background jobs immediately, rather than
     waiting until just before printing a prompt.

POSIX_JOBS <K> <S>
     This option makes job control more compliant with the POSIX
     standard.

     When the option is not set, the MONITOR option is unset on entry to
     subshells, so that job control is no longer active.  When the
     option is set, the MONITOR option and job control remain active in
     the subshell, but note that the subshell has no access to jobs in
     the parent shell.

     When the option is not set, jobs put in the background or
     foreground with bg or fg are displayed with the same information
     that would be reported by jobs.  When the option is set, only the
     text is printed.  The output from jobs itself is not affected by
     the option.

     When the option is not set, job information from the parent shell
     is saved for output within a subshell (for example, within a
     pipeline).  When the option is set, the output of jobs is empty
     until a job is started within the subshell.

     In previous versions of the shell, it was necessary to enable
     POSIX_JOBS in order for the builtin command wait to return the
     status of background jobs that had already exited.  This is no
     longer the case.

16.2.8 Prompting
----------------

PROMPT_BANG <K>
     If set, '!' is treated specially in prompt expansion.  See *note
     Expansion of Prompt Sequences::.

PROMPT_CR (+V) <D>
     Print a carriage return just before printing a prompt in the line
     editor.  This is on by default as multi-line editing is only
     possible if the editor knows where the start of the line appears.

PROMPT_SP <D>
     Attempt to preserve a partial line (i.e.  a line that did not end
     with a newline) that would otherwise be covered up by the command
     prompt due to the PROMPT_CR option.  This works by outputting some
     cursor-control characters, including a series of spaces, that
     should make the terminal wrap to the next line when a partial line
     is present (note that this is only successful if your terminal has
     automatic margins, which is typical).

     When a partial line is preserved, by default you will see an
     inverse+bold character at the end of the partial line: a '%' for a
     normal user or a '#' for root.  If set, the shell parameter
     PROMPT_EOL_MARK can be used to customize how the end of partial
     lines are shown.

     NOTE: if the PROMPT_CR option is not set, enabling this option will
     have no effect.  This option is on by default.

PROMPT_PERCENT <C> <Z>
     If set, '%' is treated specially in prompt expansion.  See *note
     Expansion of Prompt Sequences::.

PROMPT_SUBST <K> <S>
     If set, _parameter expansion_, _command substitution_ and
     _arithmetic expansion_ are performed in prompts.  Substitutions
     within prompts do not affect the command status.

TRANSIENT_RPROMPT
     Remove any right prompt from display when accepting a command line.
     This may be useful with terminals with other cut/paste methods.

16.2.9 Scripts and Functions
----------------------------

ALIAS_FUNC_DEF <S>
     By default, zsh does not allow the definition of functions using
     the 'NAME ()' syntax if NAME was expanded as an alias: this causes
     an error.  This is usually the desired behaviour, as otherwise the
     combination of an alias and a function based on the same definition
     can easily cause problems.

     When this option is set, aliases can be used for defining
     functions.

     For example, consider the following definitions as they might occur
     in a startup file.

          alias foo=bar
          foo() {
            print This probably does not do what you expect.
          }

     Here, foo is expanded as an alias to bar before the () is
     encountered, so the function defined would be named bar.  By
     default this is instead an error in native mode.  Note that quoting
     any part of the function name, or using the keyword function,
     avoids the problem, so is recommended when the function name can
     also be an alias.

C_BASES
     Output hexadecimal numbers in the standard C format, for example
     '0xFF' instead of the usual '16#FF'.  If the option OCTAL_ZEROES is
     also set (it is not by default), octal numbers will be treated
     similarly and hence appear as '077' instead of '8#77'.  This option
     has no effect on the choice of the output base, nor on the output
     of bases other than hexadecimal and octal.  Note that these formats
     will be understood on input irrespective of the setting of C_BASES.

C_PRECEDENCES
     This alters the precedence of arithmetic operators to be more like
     C and other programming languages; *note Arithmetic Evaluation::
     has an explicit list.

DEBUG_BEFORE_CMD <D>
     Run the DEBUG trap before each command; otherwise it is run after
     each command.  Setting this option mimics the behaviour of ksh 93;
     with the option unset the behaviour is that of ksh 88.

ERR_EXIT (-e, ksh: -e)
     If a command has a non-zero exit status, execute the ZERR trap, if
     set, and exit.

     The option is ignored when executing the commands following while,
     until, if, or elif, a pipeline beginning with !, or any command
     other than the last in command list containing && or ||.  Hence
     neither 'if foo; then true; fi', nor 'foo && true' trigger exit
     when foo returns with a non-zero exit status.  Note that if foo is
     a function, the option is also ignored during its whole execution.

     The option is also ignored when executing a complex command (if,
     for, while, until, repeat, case, select, always, or a list in
     braces) if its exit status comes from a command executed while the
     option is ignored.  Hence, the if command in 'if true; then false
     && true; fi' does not trigger exit.

     Finally, the option is also ignored while running initialization
     scripts and inside DEBUG traps.  In the latter case, the option is
     handled specially: it is unset on entry to the trap.  If the option
     DEBUG_BEFORE_CMD is set, as it is by default, and the option
     ERR_EXIT is found to have been set on exit, then the command for
     which the DEBUG trap is being executed is skipped.  The option is
     restored after the trap exits.

     Exiting due to ERR_EXIT has certain interactions with asynchronous
     jobs noted in *note Signals::.

     Note this behaviour is not disabled in interactive shells -- a
     non-zero status on the command line causes the shell to exit.

ERR_RETURN
     If a command has a non-zero exit status, return immediately from
     the enclosing function.  Except as explained below, an implicit
     return statement is executed following the same logic described for
     ERR_EXIT.  This will trigger an exit at the outermost level of a
     non-interactive script.  At the top level of an interactive shell,
     it will trigger a return to the command prompt; in other words, the
     sequence of commands typed by the user may be thought of as a
     function for this purpose.

     Unlike for ERR_EXIT, when a function is called while the option is
     being ignored, the option is NOT ignored during the execution of
     the function.  Hence, if foo in 'foo && true' is a function, code
     inside it is considered separately: it may force a return from foo
     (assuming the option remains set within foo).

     Like for ERR_EXIT, the option is ignored inside DEBUG traps but
     it's not unset on entry to the trap and setting or unsetting it
     inside the trap has no special effect.

     If ERR_RETURN and ERR_EXIT are both set, it may happen that both
     exit and return should be triggered.  In that case only exit is
     triggered.

EVAL_LINENO <Z>
     If set, line numbers of expressions evaluated using the builtin
     eval are tracked separately of the enclosing environment.  This
     applies both to the parameter LINENO and the line number output by
     the prompt escape %i.  If the option is set, the prompt escape %N
     will output the string '(eval)' instead of the script or function
     name as an indication.  (The two prompt escapes are typically used
     in the parameter PS4 to be output when the option XTRACE is set.)
     If EVAL_LINENO is unset, the line number of the surrounding script
     or function is retained during the evaluation.

EXEC (+n, ksh: +n) <D>
     Do execute commands.  Without this option, commands are read and
     checked for syntax errors, but not executed.  This option cannot be
     turned off in an interactive shell, except when '-n' is supplied to
     the shell at startup.

FUNCTION_ARGZERO <C> <Z>
     When executing a shell function or sourcing a script, set $0
     temporarily to the name of the function/script.  Note that toggling
     FUNCTION_ARGZERO from on to off (or off to on) does not change the
     current value of $0.  Only the state upon entry to the function or
     script has an effect.  Compare POSIX_ARGZERO.

LOCAL_LOOPS
     When this option is not set, the effect of break and continue
     commands may propagate outside function scope, affecting loops in
     calling functions.  When the option is set in a calling function, a
     break or a continue that is not caught within a called function
     (regardless of the setting of the option within that function)
     produces a warning and the effect is cancelled.

LOCAL_OPTIONS <K>
     If this option is set at the point of return from a shell function,
     most options (including this one) which were in force upon entry to
     the function are restored; options that are not restored are
     PRIVILEGED and RESTRICTED.  Otherwise, only this option, and the
     LOCAL_LOOPS, XTRACE and PRINT_EXIT_VALUE options are restored.
     Hence if this is explicitly unset by a shell function the other
     options in force at the point of return will remain so.  A shell
     function can also guarantee itself a known shell configuration with
     a formulation like 'emulate -L zsh'; the -L activates
     LOCAL_OPTIONS.

LOCAL_PATTERNS
     If this option is set at the point of return from a shell function,
     the state of pattern disables, as set with the builtin command
     'disable -p', is restored to what it was when the function was
     entered.  The behaviour of this option is similar to the effect of
     LOCAL_OPTIONS on options; hence 'emulate -L sh' (or indeed any
     other emulation with the -L option) activates LOCAL_PATTERNS.

LOCAL_TRAPS <K>
     If this option is set when a signal trap is set inside a function,
     then the previous status of the trap for that signal will be
     restored when the function exits.  Note that this option must be
     set _prior_ to altering the trap behaviour in a function; unlike
     LOCAL_OPTIONS, the value on exit from the function is irrelevant.
     However, it does not need to be set before any global trap for that
     to be correctly restored by a function.  For example,

          unsetopt localtraps
          trap - INT
          fn() { setopt localtraps; trap '' INT; sleep 3; }

     will restore normal handling of SIGINT after the function exits.

MULTI_FUNC_DEF <Z>
     Allow definitions of multiple functions at once in the form 'fn1
     fn2...()'; if the option is not set, this causes a parse error.
     Definition of multiple functions with the function keyword is
     always allowed.  Multiple function definitions are not often used
     and can cause obscure errors.

     Note that no error is raised if multiple functions are defined as a
     result of a set of names that were originally read as a single word
     on the command line, for example 'TRAP{INT,QUIT}'.  Although there
     are no plans to change this behaviour at present, it is not
     guaranteed.

MULTIOS <Z>
     Perform implicit ‘tee’s or ‘cat’s when multiple redirections are
     attempted (see *note Redirection::).

OCTAL_ZEROES <S>
     Interpret any integer constant beginning with a 0 as octal, per
     IEEE Std 1003.2-1992 (ISO 9945-2:1993).  This is not enabled by
     default as it causes problems with parsing of, for example, date
     and time strings with leading zeroes.

     Sequences of digits indicating a numeric base such as the '08'
     component in '08#77' are always interpreted as decimal, regardless
     of leading zeroes.

PIPE_FAIL
     By default, when a pipeline exits the exit status recorded by the
     shell and returned by the shell variable $? reflects that of the
     rightmost element of a pipeline.  If this option is set, the exit
     status instead reflects the status of the rightmost element of the
     pipeline that was non-zero, or zero if all elements exited with
     zero status.

SOURCE_TRACE
     If set, zsh will print an informational message announcing the name
     of each file it loads.  The format of the output is similar to that
     for the XTRACE option, with the message <sourcetrace>.  A file may
     be loaded by the shell itself when it starts up and shuts down
     (Startup/Shutdown Files) or by the use of the 'source' and 'dot'
     builtin commands.

TYPESET_SILENT
     If this is unset, executing any of the 'typeset' family of commands
     with no options and a list of parameters that have no values to be
     assigned but already exist will display the value of the parameter.
     If the option is set, they will only be shown when parameters are
     selected with the '-m' option.  The option '-p' is available
     whether or not the option is set.

TYPESET_TO_UNSET <K> <S>
     When declaring a new parameter with any of the 'typeset' family of
     related commands, the parameter remains unset unless and until a
     value is explicitly assigned to it, either in the 'typeset' command
     itself or as a later assignment statement.

VERBOSE (-v, ksh: -v)
     Print shell input lines as they are read.

XTRACE (-x, ksh: -x)
     Print commands and their arguments as they are executed.  The
     output is preceded by the value of $PS4, formatted as described in
     *note Expansion of Prompt Sequences::.

16.2.10 Shell Emulation
-----------------------

APPEND_CREATE <K> <S>
     This option only applies when NO_CLOBBER (-C) is in effect.

     If this option is not set, the shell will report an error when a
     append redirection (>>) is used on a file that does not already
     exists (the traditional zsh behaviour of NO_CLOBBER).  If the
     option is set, no error is reported (POSIX behaviour).

BASH_REMATCH
     When set, matches performed with the =~ operator will set the
     BASH_REMATCH array variable, instead of the default MATCH and match
     variables.  The first element of the BASH_REMATCH array will
     contain the entire matched text and subsequent elements will
     contain extracted substrings.  This option makes more sense when
     KSH_ARRAYS is also set, so that the entire matched portion is
     stored at index 0 and the first substring is at index 1.  Without
     this option, the MATCH variable contains the entire matched text
     and the match array variable contains substrings.

BSD_ECHO <S>
     Make the echo builtin compatible with the BSD echo(1) command.
     This disables backslashed escape sequences in echo strings unless
     the -e option is specified.

CONTINUE_ON_ERROR
     If a fatal error is encountered (see *note Errors::), and the code
     is running in a script, the shell will resume execution at the next
     statement in the script at the top level, in other words outside
     all functions or shell constructs such as loops and conditions.
     This mimics the behaviour of interactive shells, where the shell
     returns to the line editor to read a new command; it was the normal
     behaviour in versions of zsh before 5.0.1.

CSH_JUNKIE_HISTORY <C>
     A history reference without an event specifier will always refer to
     the previous command.  Without this option, such a history
     reference refers to the same event as the previous history
     reference on the current command line, defaulting to the previous
     command.

CSH_JUNKIE_LOOPS <C>
     Allow loop bodies to take the form 'LIST; end' instead of 'do LIST;
     done'.

CSH_JUNKIE_QUOTES <C>
     Changes the rules for single- and double-quoted text to match that
     of ‘csh’.  These require that embedded newlines be preceded by a
     backslash; unescaped newlines will cause an error message.  In
     double-quoted strings, it is made impossible to escape '$', '`' or
     '"' (and '\' itself no longer needs escaping).  Command
     substitutions are only expanded once, and cannot be nested.

CSH_NULLCMD <C>
     Do not use the values of NULLCMD and READNULLCMD when running
     redirections with no command.  This make such redirections fail
     (see *note Redirection::).

KSH_ARRAYS <K> <S>
     Emulate ‘ksh’ array handling as closely as possible.  If this
     option is set, array elements are numbered from zero, an array
     parameter without subscript refers to the first element instead of
     the whole array, and braces are required to delimit a subscript
     ('${path[2]}' rather than just '$path[2]') or to apply modifiers to
     any parameter ('${PWD:h}' rather than '$PWD:h').

KSH_AUTOLOAD <K> <S>
     Emulate ‘ksh’ function autoloading.  This means that when a
     function is autoloaded, the corresponding file is merely executed,
     and must define the function itself.  (By default, the function is
     defined to the contents of the file.  However, the most common
     ‘ksh’-style case - of the file containing only a simple definition
     of the function - is always handled in the ‘ksh’-compatible
     manner.)

KSH_OPTION_PRINT <K>
     Alters the way options settings are printed: instead of separate
     lists of set and unset options, all options are shown, marked 'on'
     if they are in the non-default state, 'off' otherwise.

KSH_TYPESET
     This option is now obsolete: a better appropximation to the
     behaviour of other shells is obtained with the reserved word
     interface to declare, export, float, integer, local, readonly and
     typeset.  Note that the option is only applied when the reserved
     word interface is _not_ in use.

     Alters the way arguments to the typeset family of commands,
     including declare, export, float, integer, local and readonly, are
     processed.  Without this option, zsh will perform normal word
     splitting after command and parameter expansion in arguments of an
     assignment; with it, word splitting does not take place in those
     cases.

KSH_ZERO_SUBSCRIPT
     Treat use of a subscript of value zero in array or string
     expressions as a reference to the first element, i.e.  the element
     that usually has the subscript 1.  Ignored if KSH_ARRAYS is also
     set.

     If neither this option nor KSH_ARRAYS is set, accesses to an
     element of an array or string with subscript zero return an empty
     element or string, while attempts to set element zero of an array
     or string are treated as an error.  However, attempts to set an
     otherwise valid subscript range that includes zero will succeed.
     For example, if KSH_ZERO_SUBSCRIPT is not set,

          array[0]=(element)

     is an error, while

          array[0,1]=(element)

     is not and will replace the first element of the array.

     This option is for compatibility with older versions of the shell
     and is not recommended in new code.

POSIX_ALIASES <K> <S>
     When this option is set, reserved words are not candidates for
     alias expansion: it is still possible to declare any of them as an
     alias, but the alias will never be expanded.  Reserved words are
     described in *note Reserved Words::.

     Alias expansion takes place while text is being read; hence when
     this option is set it does not take effect until the end of any
     function or other piece of shell code parsed as one unit.  Note
     this may cause differences from other shells even when the option
     is in effect.  For example, when running a command with 'zsh -c',
     or even 'zsh -o posixaliases -c', the entire command argument is
     parsed as one unit, so aliases defined within the argument are not
     available even in later lines.  If in doubt, avoid use of aliases
     in non-interactive code.

POSIX_ARGZERO
     This option may be used to temporarily disable FUNCTION_ARGZERO and
     thereby restore the value of $0 to the name used to invoke the
     shell (or as set by the -c command line option).  For compatibility
     with previous versions of the shell, emulations use
     NO_FUNCTION_ARGZERO instead of POSIX_ARGZERO, which may result in
     unexpected scoping of $0 if the emulation mode is changed inside a
     function or script.  To avoid this, explicitly enable POSIX_ARGZERO
     in the emulate command:

          emulate sh -o POSIX_ARGZERO

     Note that NO_POSIX_ARGZERO has no effect unless FUNCTION_ARGZERO
     was already enabled upon entry to the function or script.

POSIX_BUILTINS <K> <S>
     When this option is set the command builtin can be used to execute
     shell builtin commands.  Parameter assignments specified before
     shell functions and special builtins are kept after the command
     completes unless the special builtin is prefixed with the command
     builtin.  Special builtins are ., :, break, continue, declare,
     eval, exit, export, integer, local, readonly, return, set, shift,
     source, times, trap and unset.

     In addition, various error conditions associated with the above
     builtins or exec cause a non-interactive shell to exit and an
     interactive shell to return to its top-level processing.

     Furthermore, functions and shell builtins are not executed after an
     exec prefix; the command to be executed must be an external command
     found in the path.

     Furthermore, the getopts builtin behaves in a POSIX-compatible
     fashion in that the associated variable OPTIND is not made local to
     functions, and its value is calculated differently to match other
     shells.

     Moreover, the warning and special exit code from [[ -o
     NON_EXISTENT_OPTION ]] are suppressed.

POSIX_IDENTIFIERS <K> <S>
     When this option is set, only the ASCII characters a to z, A to Z,
     0 to 9 and _ may be used in identifiers (names of shell parameters
     and modules).

     In addition, setting this option limits the effect of parameter
     substitution with no braces, so that the expression $# is treated
     as the parameter $# even if followed by a valid parameter name.
     When it is unset, zsh allows expressions of the form $#NAME to
     refer to the length of $NAME, even for special variables, for
     example in expressions such as $#- and $#*.

     Another difference is that with the option set assignment to an
     unset variable in arithmetic context causes the variable to be
     created as a scalar rather than a numeric type.  So after 'unset t;
     (( t = 3 ))'.  without POSIX_IDENTIFIERS set t has integer type,
     while with it set it has scalar type.

     When the option is unset and multibyte character support is enabled
     (i.e.  it is compiled in and the option MULTIBYTE is set), then
     additionally any alphanumeric characters in the local character set
     may be used in identifiers.  Note that scripts and functions
     written with this feature are not portable, and also that both
     options must be set before the script or function is parsed;
     setting them during execution is not sufficient as the syntax
     VARIABLE=VALUE has already been parsed as a command rather than an
     assignment.

     If multibyte character support is not compiled into the shell this
     option is ignored; all octets with the top bit set may be used in
     identifiers.  This is non-standard but is the traditional zsh
     behaviour.

POSIX_STRINGS <K> <S>
     This option affects processing of quoted strings.  Currently it
     only affects the behaviour of null characters, i.e.  character 0 in
     the portable character set corresponding to US ASCII.

     When this option is not set, null characters embedded within
     strings of the form $'...' are treated as ordinary characters.  The
     entire string is maintained within the shell and output to files
     where necessary, although owing to restrictions of the library
     interface the string is truncated at the null character in file
     names, environment variables, or in arguments to external programs.

     When this option is set, the $'...' expression is truncated at the
     null character.  Note that remaining parts of the same string
     beyond the termination of the quotes are not truncated.

     For example, the command line argument a$'b\0c'd is treated with
     the option off as the characters a, b, null, c, d, and with the
     option on as the characters a, b, d.

POSIX_TRAPS <K> <S>
     When this option is set, the usual zsh behaviour of executing traps
     for EXIT on exit from shell functions is suppressed.  In that case,
     manipulating EXIT traps always alters the global trap for exiting
     the shell; the LOCAL_TRAPS option is ignored for the EXIT trap.

     Also, a return statement executed in a trap with no argument passes
     back from the function the value from the surrounding context, not
     from code executed within the trap.

     Furthermore, if a trap is set to be ignored, this state persists
     when a subshell is entered.  Without the option, the trap would be
     reset to its default state at this point.

SH_FILE_EXPANSION <K> <S>
     Perform filename expansion (e.g., ~ expansion) _before_ parameter
     expansion, command substitution, arithmetic expansion and brace
     expansion.  If this option is unset, it is performed _after_ brace
     expansion, so things like '~$USERNAME' and '~{pfalstad,rc}' will
     work.

SH_NULLCMD <K> <S>
     Do not use the values of NULLCMD and READNULLCMD when doing
     redirections, use ':' instead (see *note Redirection::).

SH_OPTION_LETTERS <K> <S>
     If this option is set the shell tries to interpret single letter
     options (which are used with set and setopt) like ‘ksh’ does.  This
     also affects the value of the - special parameter.

SH_WORD_SPLIT (-y) <K> <S>
     Causes field splitting to be performed on unquoted parameter
     expansions.  Note that this option has nothing to do with word
     splitting.  (See *note Parameter Expansion::.)

TRAPS_ASYNC
     While waiting for a program to exit, handle signals and run traps
     immediately.  Otherwise the trap is run after a child process has
     exited.  Note this does not affect the point at which traps are run
     for any case other than when the shell is waiting for a child
     process.

16.2.11 Shell State
-------------------

INTERACTIVE (-i, ksh: -i)
     This is an interactive shell.  This option is set upon
     initialisation if the standard input is a tty and commands are
     being read from standard input.  (See the discussion of
     SHIN_STDIN.)  This heuristic may be overridden by specifying a
     state for this option on the command line.  The value of this
     option can only be changed via flags supplied at invocation of the
     shell.  It cannot be changed once zsh is running.

LOGIN (-l, ksh: -l)
     This is a login shell.  If this option is not explicitly set, the
     shell becomes a login shell if the first character of the argv[0]
     passed to the shell is a '-'.

PRIVILEGED (-p, ksh: -p)
     Turn on privileged mode.  Typically this is used when script is to
     be run with elevated privileges.  This should be done as follows
     directly with the -p option to zsh so that it takes effect during
     startup.

          #!/bin/zsh -p

     The option is enabled automatically on startup if the effective
     user (group) ID is not equal to the real user (group) ID. In this
     case, turning the option off causes the effective user and group
     IDs to be set to the real user and group IDs.  Be aware that if
     that fails the shell may be running with different IDs than was
     intended so a script should check for failure and act accordingly,
     for example:

          unsetopt privileged || exit

     The PRIVILEGED option disables sourcing user startup files.  If zsh
     is invoked as 'sh' or 'ksh' with this option set, /etc/suid_profile
     is sourced (after /etc/profile on interactive shells).  Sourcing
     ~/.profile is disabled and the contents of the ENV variable is
     ignored.  This option cannot be changed using the -m option of
     setopt and unsetopt, and changing it inside a function always
     changes it globally regardless of the LOCAL_OPTIONS option.

RESTRICTED (-r)
     Enables restricted mode.  This option cannot be changed using
     unsetopt, and setting it inside a function always changes it
     globally regardless of the LOCAL_OPTIONS option.  See *note
     Restricted Shell::.

SHIN_STDIN (-s, ksh: -s)
     Commands are being read from the standard input.  Commands are read
     from standard input if no command is specified with -c and no file
     of commands is specified.  If SHIN_STDIN is set explicitly on the
     command line, any argument that would otherwise have been taken as
     a file to run will instead be treated as a normal positional
     parameter.  Note that setting or unsetting this option on the
     command line does not necessarily affect the state the option will
     have while the shell is running - that is purely an indicator of
     whether or not commands are _actually_ being read from standard
     input.  The value of this option can only be changed via flags
     supplied at invocation of the shell.  It cannot be changed once zsh
     is running.

SINGLE_COMMAND (-t, ksh: -t)
     If the shell is reading from standard input, it exits after a
     single command has been executed.  This also makes the shell
     non-interactive, unless the INTERACTIVE option is explicitly set on
     the command line.  The value of this option can only be changed via
     flags supplied at invocation of the shell.  It cannot be changed
     once zsh is running.

16.2.12 Zle
-----------

BEEP (+B) <D>
     Beep on error in ZLE.

COMBINING_CHARS
     Assume that the terminal displays combining characters correctly.
     Specifically, if a base alphanumeric character is followed by one
     or more zero-width punctuation characters, assume that the
     zero-width characters will be displayed as modifications to the
     base character within the same width.  Not all terminals handle
     this.  If this option is not set, zero-width characters are
     displayed separately with special mark-up.

     If this option is set, the pattern test [[:WORD:]] matches a
     zero-width punctuation character on the assumption that it will be
     used as part of a word in combination with a word character.
     Otherwise the base shell does not handle combining characters
     specially.

EMACS
     If ZLE is loaded, turning on this option has the equivalent effect
     of 'bindkey -e'.  In addition, the VI option is unset.  Turning it
     off has no effect.  The option setting is not guaranteed to reflect
     the current keymap, and the LOCALOPTIONS option does not work
     correctly.  This option is provided only for compatibility, and its
     use is highly discouraged.  bindkey is the recommended interface.

OVERSTRIKE
     Start up the line editor in overstrike mode.

SINGLE_LINE_ZLE (-M) <K>
     Use single-line command line editing instead of multi-line.

     Note that although this is on by default in ksh emulation it only
     provides superficial compatibility with the ksh line editor and
     reduces the effectiveness of the zsh line editor.  As it has no
     effect on shell syntax, many users may wish to disable this option
     when using ksh emulation interactively.

VI
     If ZLE is loaded, turning on this option has the equivalent effect
     of 'bindkey -v'.  In addition, the EMACS option is unset.  Turning
     it off has no effect.  The option setting is not guaranteed to
     reflect the current keymap, and the LOCALOPTIONS option does not
     work correctly.  This option is provided only for compatibility,
     and its use is highly discouraged.  bindkey is the recommended
     interface.

ZLE (-Z)
     Use the zsh line editor.  Set by default in interactive shells
     connected to a terminal.


File: zsh.info,  Node: Option Aliases,  Next: Single Letter Options,  Prev: Description of Options,  Up: Options

16.3 Option Aliases
===================

Some options have alternative names.  These aliases are never used for
output, but can be used just like normal option names when specifying
options to the shell.

BRACE_EXPAND
     _NO__IGNORE_BRACES (ksh and bash compatibility)

DOT_GLOB
     GLOB_DOTS (bash compatibility)

HASH_ALL
     HASH_CMDS (bash compatibility)

HIST_APPEND
     APPEND_HISTORY (bash compatibility)

HIST_EXPAND
     BANG_HIST (bash compatibility)

LOG
     _NO__HIST_NO_FUNCTIONS (ksh compatibility)

MAIL_WARN
     MAIL_WARNING (bash compatibility)

ONE_CMD
     SINGLE_COMMAND (bash compatibility)

PHYSICAL
     CHASE_LINKS (ksh and bash compatibility)

PROMPT_VARS
     PROMPT_SUBST (bash compatibility)

STDIN
     SHIN_STDIN (ksh compatibility)

TRACK_ALL
     HASH_CMDS (ksh compatibility)


File: zsh.info,  Node: Single Letter Options,  Prev: Option Aliases,  Up: Options

16.4 Single Letter Options
==========================

16.4.1 Default Set
------------------

-0
     CORRECT
-1
     PRINT_EXIT_VALUE
-2
     _NO__BAD_PATTERN
-3
     _NO__NOMATCH
-4
     GLOB_DOTS
-5
     NOTIFY
-6
     BG_NICE
-7
     IGNORE_EOF
-8
     MARK_DIRS
-9
     AUTO_LIST
-B
     _NO__BEEP
-C
     _NO__CLOBBER
-D
     PUSHD_TO_HOME
-E
     PUSHD_SILENT
-F
     _NO__GLOB
-G
     NULL_GLOB
-H
     RM_STAR_SILENT
-I
     IGNORE_BRACES
-J
     AUTO_CD
-K
     _NO__BANG_HIST
-L
     SUN_KEYBOARD_HACK
-M
     SINGLE_LINE_ZLE
-N
     AUTO_PUSHD
-O
     CORRECT_ALL
-P
     RC_EXPAND_PARAM
-Q
     PATH_DIRS
-R
     LONG_LIST_JOBS
-S
     REC_EXACT
-T
     CDABLE_VARS
-U
     MAIL_WARNING
-V
     _NO__PROMPT_CR
-W
     AUTO_RESUME
-X
     LIST_TYPES
-Y
     MENU_COMPLETE
-Z
     ZLE
-a
     ALL_EXPORT
-e
     ERR_EXIT
-f
     _NO__RCS
-g
     HIST_IGNORE_SPACE
-h
     HIST_IGNORE_DUPS
-i
     INTERACTIVE
-k
     INTERACTIVE_COMMENTS
-l
     LOGIN
-m
     MONITOR
-n
     _NO__EXEC
-p
     PRIVILEGED
-r
     RESTRICTED
-s
     SHIN_STDIN
-t
     SINGLE_COMMAND
-u
     _NO__UNSET
-v
     VERBOSE
-w
     CHASE_LINKS
-x
     XTRACE
-y
     SH_WORD_SPLIT

16.4.2 sh/ksh Emulation Set
---------------------------

-C
     _NO__CLOBBER
-T
     TRAPS_ASYNC
-X
     MARK_DIRS
-a
     ALL_EXPORT
-b
     NOTIFY
-e
     ERR_EXIT
-f
     _NO__GLOB
-i
     INTERACTIVE
-l
     LOGIN
-m
     MONITOR
-n
     _NO__EXEC
-p
     PRIVILEGED
-r
     RESTRICTED
-s
     SHIN_STDIN
-t
     SINGLE_COMMAND
-u
     _NO__UNSET
-v
     VERBOSE
-x
     XTRACE

16.4.3 Also Note
----------------

-A
     Used by set for setting arrays
-b
     Used on the command line to specify end of option processing
-c
     Used on the command line to specify a single command
-m
     Used by setopt for pattern-matching option setting
-o
     Used in all places to allow use of long option names
-s
     Used by set to sort positional parameters


File: zsh.info,  Node: Shell Builtin Commands,  Next: Zsh Line Editor,  Prev: Options,  Up: Top

17 Shell Builtin Commands
*************************

Some shell builtin commands take options as described in individual
entries; these are often referred to in the list below as 'flags' to
avoid confusion with shell options, which may also have an effect on the
behaviour of builtin commands.  In this introductory section, 'option'
always has the meaning of an option to a command that should be familiar
to most command line users.

Typically, options are single letters preceded by a hyphen (-).  Options
that take an argument accept it either immediately following the option
letter or after white space, for example 'print -C3 {1..9}' or 'print -C
3 {1..9}' are equivalent.  Arguments to options are not the same as
arguments to the command; the documentation indicates which is which.
Options that do not take an argument may be combined in a single word,
for example 'print -rca -- *' and 'print -r -c -a -- *' are equivalent.

Some shell builtin commands also take options that begin with '+'
instead of '-'.  The list below makes clear which commands these are.

Options (together with their individual arguments, if any) must appear
in a group before any non-option arguments; once the first non-option
argument has been found, option processing is terminated.

All builtin commands other than 'echo' and precommand modifiers, even
those that have no options, can be given the argument '--' to terminate
option processing.  This indicates that the following words are
non-option arguments, but is otherwise ignored.  This is useful in cases
where arguments to the command may begin with '-'.  For historical
reasons, most builtin commands (including 'echo') also recognize a
single '-' in a separate word for this purpose; note that this is less
standard and use of '--' is recommended.

- SIMPLE COMMAND
     See *note Precommand Modifiers::.

. FILE [ ARG ... ]
     Read commands from FILE and execute them in the current shell
     environment.

     If FILE does not contain a slash, or if PATH_DIRS is set, the shell
     looks in the components of $path to find the directory containing
     FILE.  Files in the current directory are not read unless '.'
     appears somewhere in $path.  If a file named 'FILE.zwc' is found,
     is newer than FILE, and is the compiled form (created with the
     zcompile builtin) of FILE, then commands are read from that file
     instead of FILE.

     If any arguments ARG are given, they become the positional
     parameters; the old positional parameters are restored when the
     FILE is done executing.  However, if no arguments are given, the
     positional parameters remain those of the calling context, and no
     restoring is done.

     If FILE was not found the return status is 127; if FILE was found
     but contained a syntax error the return status is 126; else the
     return status is the exit status of the last command executed.

: [ ARG ... ]
     This command does nothing, although normal argument expansions is
     performed which may have effects on shell parameters.  A zero exit
     status is returned.

alias [ {+|-}gmrsL ] [ NAME[=VALUE] ... ]
     For each NAME with a corresponding VALUE, define an alias with that
     value.  A trailing space in VALUE causes the next word to be
     checked for alias expansion.  If the -g flag is present, define a
     global alias; global aliases are expanded even if they do not occur
     in command position:

          % perldoc --help 2>&1 | grep 'built-in functions'
              -f   Search Perl built-in functions
          % alias -g HG='--help 2>&1 | grep'
          % perldoc HG 'built-in functions'
              -f   Search Perl built-in functions

     If the -s flag is present, define a suffix alias: if the command
     word on a command line is in the form 'TEXT.NAME', where TEXT is
     any non-empty string, it is replaced by the text 'VALUE TEXT.NAME'.
     Note that NAME is treated as a literal string, not a pattern.  A
     trailing space in VALUE is not special in this case.  For example,

          alias -s ps='gv --'

     will cause the command '*.ps' to be expanded to 'gv -- *.ps'.  As
     alias expansion is carried out earlier than globbing, the '*.ps'
     will then be expanded.  Suffix aliases constitute a different name
     space from other aliases (so in the above example it is still
     possible to create an alias for the command ps) and the two sets
     are never listed together.

     For each NAME with no VALUE, print the value of NAME, if any.  With
     no arguments, print all currently defined aliases other than suffix
     aliases.  If the -m flag is given the arguments are taken as
     patterns (they should be quoted to preserve them from being
     interpreted as glob patterns), and the aliases matching these
     patterns are printed.  When printing aliases and one of the -g, -r
     or -s flags is present, restrict the printing to global, regular or
     suffix aliases, respectively; a regular alias is one which is
     neither a global nor a suffix alias.  Using '+' instead of '-', or
     ending the option list with a single '+', prevents the values of
     the aliases from being printed.

     If the -L flag is present, then print each alias in a manner
     suitable for putting in a startup script.  The exit status is
     nonzero if a NAME (with no VALUE) is given for which no alias has
     been defined.

     For more on aliases, including common problems, see *note
     Aliasing::.

autoload [ {+|-}RTUXdkmrtWz ] [ -w ] [ NAME ... ]
     See *note Autoloading Functions:: for full details.  The fpath
     parameter will be searched to find the function definition when the
     function is first referenced.

     If NAME consists of an absolute path, the function is defined to
     load from the file given (searching as usual for dump files in the
     given location).  The name of the function is the basename
     (non-directory part) of the file.  It is normally an error if the
     function is not found in the given location; however, if the option
     -d is given, searching for the function defaults to $fpath.  If a
     function is loaded by absolute path, any functions loaded from it
     that are marked for autoload without an absolute path have the load
     path of the parent function temporarily prepended to $fpath.

     If the option -r or -R is given, the function is searched for
     immediately and the location is recorded internally for use when
     the function is executed; a relative path is expanded using the
     value of $PWD.  This protects against a change to $fpath after the
     call to autoload.  With -r, if the function is not found, it is
     silently left unresolved until execution; with -R, an error message
     is printed and command processing aborted immediately the search
     fails, i.e.  at the autoload command rather than at function
     execution..

     The flag -X may be used only inside a shell function.  It causes
     the calling function to be marked for autoloading and then
     immediately loaded and executed, with the current array of
     positional parameters as arguments.  This replaces the previous
     definition of the function.  If no function definition is found, an
     error is printed and the function remains undefined and marked for
     autoloading.  If an argument is given, it is used as a directory
     (i.e.  it does not include the name of the function) in which the
     function is to be found; this may be combined with the -d option to
     allow the function search to default to $fpath if it is not in the
     given location.

     The flag +X attempts to load each NAME as an autoloaded function,
     but does _not_ execute it.  The exit status is zero (success) if
     the function was not previously defined _and_ a definition for it
     was found.  This does _not_ replace any existing definition of the
     function.  The exit status is nonzero (failure) if the function was
     already defined or when no definition was found.  In the latter
     case the function remains undefined and marked for autoloading.  If
     ksh-style autoloading is enabled, the function created will contain
     the contents of the file plus a call to the function itself
     appended to it, thus giving normal ksh autoloading behaviour on the
     first call to the function.  If the -m flag is also given each NAME
     is treated as a pattern and all functions already marked for
     autoload that match the pattern are loaded.

     With the -t flag, turn on execution tracing; with -T, turn on
     execution tracing only for the current function, turning it off on
     entry to any called functions that do not also have tracing
     enabled.

     With the -U flag, alias expansion is suppressed when the function
     is loaded.

     With the -w flag, the NAMEs are taken as names of files compiled
     with the zcompile builtin, and all functions defined in them are
     marked for autoloading.

     The flags -z and -k mark the function to be autoloaded using the
     zsh or ksh style, as if the option KSH_AUTOLOAD were unset or were
     set, respectively.  The flags override the setting of the option at
     the time the function is loaded.

     Note that the autoload command makes no attempt to ensure the shell
     options set during the loading or execution of the file have any
     particular value.  For this, the emulate command can be used:

          emulate zsh -c 'autoload -Uz FUNC'

     arranges that when FUNC is loaded the shell is in native zsh
     emulation, and this emulation is also applied when FUNC is run.

     Some of the functions of autoload are also provided by functions -u
     or functions -U, but autoload is a more comprehensive interface.

bg [ JOB ... ]
JOB ... &
     Put each specified JOB in the background, or the current job if
     none is specified.

bindkey
     See *note Zle Builtins::.

break [ N ]
     Exit from an enclosing for, while, until, select or repeat loop.
     If an arithmetic expression N is specified, then break N levels
     instead of just one.

builtin NAME [ ARGS ... ]
     Executes the builtin NAME, with the given ARGS.

bye
     Same as exit.

cap
     See *note The zsh/cap Module::.

cd [ -qsLP ] [ ARG ]
cd [ -qsLP ] OLD NEW
cd [ -qsLP ] {+|-}N
     Change the current directory.  In the first form, change the
     current directory to ARG, or to the value of $HOME if ARG is not
     specified.  If ARG is '-', change to the previous directory.

     Otherwise, if ARG begins with a slash, attempt to change to the
     directory given by ARG.

     If ARG does not begin with a slash, the behaviour depends on
     whether the current directory '.' occurs in the list of directories
     contained in the shell parameter cdpath.  If it does not, first
     attempt to change to the directory ARG under the current directory,
     and if that fails but cdpath is set and contains at least one
     element attempt to change to the directory ARG under each component
     of cdpath in turn until successful.  If '.' occurs in cdpath, then
     cdpath is searched strictly in order so that '.' is only tried at
     the appropriate point.

     The order of testing cdpath is modified if the option POSIX_CD is
     set, as described in the documentation for the option.

     If no directory is found, the option CDABLE_VARS is set, and a
     parameter named ARG exists whose value begins with a slash, treat
     its value as the directory.  In that case, the parameter is added
     to the named directory hash table.

     The second form of cd substitutes the string NEW for the string OLD
     in the name of the current directory, and tries to change to this
     new directory.

     The third form of cd extracts an entry from the directory stack,
     and changes to that directory.  An argument of the form '+N'
     identifies a stack entry by counting from the left of the list
     shown by the dirs command, starting with zero.  An argument of the
     form '-N' counts from the right.  If the PUSHD_MINUS option is set,
     the meanings of '+' and '-' in this context are swapped.  If the
     POSIX_CD option is set, this form of cd is not recognised and will
     be interpreted as the first form.

     If the -q (quiet) option is specified, the hook function chpwd and
     the functions in the array chpwd_functions are not called.  This is
     useful for calls to cd that do not change the environment seen by
     an interactive user.

     If the -s option is specified, cd refuses to change the current
     directory if the given pathname contains symlinks.  If the -P
     option is given or the CHASE_LINKS option is set, symbolic links
     are resolved to their true values.  If the -L option is given
     symbolic links are retained in the directory (and not resolved)
     regardless of the state of the CHASE_LINKS option.

chdir
     Same as cd.

clone
     See *note The zsh/clone Module::.

command [ -pvV ] SIMPLE COMMAND
     The simple command argument is taken as an external command instead
     of a function or builtin and is executed.  If the POSIX_BUILTINS
     option is set, builtins will also be executed but certain special
     properties of them are suppressed.  The -p flag causes a default
     path to be searched instead of that in $path.  With the -v flag,
     command is similar to whence and with -V, it is equivalent to
     whence -v.

     See also *note Precommand Modifiers::.

comparguments
     See *note The zsh/computil Module::.

compcall
     See *note The zsh/compctl Module::.

compctl
     See *note The zsh/compctl Module::.

compdescribe
     See *note The zsh/computil Module::.

compfiles
     See *note The zsh/computil Module::.

compgroups
     See *note The zsh/computil Module::.

compquote
     See *note The zsh/computil Module::.

comptags
     See *note The zsh/computil Module::.

comptry
     See *note The zsh/computil Module::.

compvalues
     See *note The zsh/computil Module::.

continue [ N ]
     Resume the next iteration of the enclosing for, while, until,
     select or repeat loop.  If an arithmetic expression N is specified,
     break out of N-1 loops and resume at the Nth enclosing loop.

declare
     Same as typeset.

dirs [ -c ] [ ARG ... ]
dirs [ -lpv ]
     With no arguments, print the contents of the directory stack.
     Directories are added to this stack with the pushd command, and
     removed with the cd or popd commands.  If arguments are specified,
     load them onto the directory stack, replacing anything that was
     there, and push the current directory onto the stack.

     -c
          clear the directory stack.

     -l
          print directory names in full instead of using ~ expressions
          (see *note Filename Expansion::).

     -p
          print directory entries one per line.

     -v
          number the directories in the stack when printing.

disable [ -afmprs ] NAME ...
     Temporarily disable the NAMEd hash table elements or patterns.  The
     default is to disable builtin commands.  This allows you to use an
     external command with the same name as a builtin command.  The -a
     option causes disable to act on regular or global aliases.  The -s
     option causes disable to act on suffix aliases.  The -f option
     causes disable to act on shell functions.  The -r options causes
     disable to act on reserved words.  Without arguments all disabled
     hash table elements from the corresponding hash table are printed.
     With the -m flag the arguments are taken as patterns (which should
     be quoted to prevent them from undergoing filename expansion), and
     all hash table elements from the corresponding hash table matching
     these patterns are disabled.  Disabled objects can be enabled with
     the enable command.

     With the option -p, NAME ...  refer to elements of the shell's
     pattern syntax as described in *note Filename Generation::.
     Certain elements can be disabled separately, as given below.

     Note that patterns not allowed by the current settings for the
     options EXTENDED_GLOB, KSH_GLOB and SH_GLOB are never enabled,
     regardless of the setting here.  For example, if EXTENDED_GLOB is
     not active, the pattern ^ is ineffective even if 'disable -p "^"'
     has not been issued.  The list below indicates any option settings
     that restrict the use of the pattern.  It should be noted that
     setting SH_GLOB has a wider effect than merely disabling patterns
     as certain expressions, in particular those involving parentheses,
     are parsed differently.

     The following patterns may be disabled; all the strings need
     quoting on the command line to prevent them from being interpreted
     immediately as patterns and the patterns are shown below in single
     quotes as a reminder.

     '?'
          The pattern character ? wherever it occurs, including when
          preceding a parenthesis with KSH_GLOB.

     '*'
          The pattern character * wherever it occurs, including
          recursive globbing and when preceding a parenthesis with
          KSH_GLOB.

     '['
          Character classes.

     '<' (NO_SH_GLOB)
          Numeric ranges.

     '|' (NO_SH_GLOB)
          Alternation in grouped patterns, case statements, or KSH_GLOB
          parenthesised expressions.

     '(' (NO_SH_GLOB)
          Grouping using single parentheses.  Disabling this does not
          disable the use of parentheses for KSH_GLOB where they are
          introduced by a special character, nor for glob qualifiers
          (use 'setopt NO_BARE_GLOB_QUAL' to disable glob qualifiers
          that use parentheses only).

     '~' (EXTENDED_GLOB)
          Exclusion in the form A~B.

     '^' (EXTENDED_GLOB)
          Exclusion in the form A^B.

     '#' (EXTENDED_GLOB)
          The pattern character # wherever it occurs, both for
          repetition of a previous pattern and for indicating globbing
          flags.

     '?(' (KSH_GLOB)
          The grouping form ?(...).  Note this is also disabled if '?'
          is disabled.

     '*(' (KSH_GLOB)
          The grouping form *(...).  Note this is also disabled if '*'
          is disabled.

     '+(' (KSH_GLOB)
          The grouping form +(...).

     '!(' (KSH_GLOB)
          The grouping form !(...).

     '@(' (KSH_GLOB)
          The grouping form @(...).

disown [ JOB ... ]
JOB ... &|
JOB ... &!
     Remove the specified JOBs from the job table; the shell will no
     longer report their status, and will not complain if you try to
     exit an interactive shell with them running or stopped.  If no JOB
     is specified, disown the current job.

     If the JOBs are currently stopped and the AUTO_CONTINUE option is
     not set, a warning is printed containing information about how to
     make them running after they have been disowned.  If one of the
     latter two forms is used, the JOBs will automatically be made
     running, independent of the setting of the AUTO_CONTINUE option.

echo [ -neE ] [ ARG ... ]
     Write each ARG on the standard output, with a space separating each
     one.  If the -n flag is not present, print a newline at the end.
     echo recognizes the following escape sequences:

     \a
          bell character
     \b
          backspace
     \c
          suppress subsequent characters and final newline
     \e
          escape
     \f
          form feed
     \n
          linefeed (newline)
     \r
          carriage return
     \t
          horizontal tab
     \v
          vertical tab
     \\
          backslash
     \0NNN
          character code in octal
     \xNN
          character code in hexadecimal
     \uNNNN
          unicode character code in hexadecimal
     \UNNNNNNNN
          unicode character code in hexadecimal

     The -E flag, or the BSD_ECHO option, can be used to disable these
     escape sequences.  In the latter case, -e flag can be used to
     enable them.

     Note that for standards compliance a double dash does not terminate
     option processing; instead, it is printed directly.  However, a
     single dash does terminate option processing, so the first dash,
     possibly following options, is not printed, but everything
     following it is printed as an argument.  The single dash behaviour
     is different from other shells.  For a more portable way of
     printing text, see printf, and for a more controllable way of
     printing text within zsh, see print.

echotc
     See *note The zsh/termcap Module::.

echoti
     See *note The zsh/terminfo Module::.

emulate [ -lLR ] [ {zsh|sh|ksh|csh} [ FLAGS ... ] ]
     Without any argument print current emulation mode.

     With single argument set up zsh options to emulate the specified
     shell as much as possible.  ‘csh’ will never be fully emulated.  If
     the argument is not one of the shells listed above, zsh will be
     used as a default; more precisely, the tests performed on the
     argument are the same as those used to determine the emulation at
     startup based on the shell name, see *note Compatibility::.  In
     addition to setting shell options, the command also restores the
     pristine state of pattern enables, as if all patterns had been
     enabled using enable -p.

     If the emulate command occurs inside a function that has been
     marked for execution tracing with functions -t then the xtrace
     option will be turned on regardless of emulation mode or other
     options.  Note that code executed inside the function by the .,
     source, or eval commands is not considered to be running directly
     from the function, hence does not provoke this behaviour.

     If the -R switch is given, all settable options are reset to their
     default value corresponding to the specified emulation mode, except
     for certain options describing the interactive environment;
     otherwise, only those options likely to cause portability problems
     in scripts and functions are altered.  If the -L switch is given,
     the options LOCAL_OPTIONS, LOCAL_PATTERNS and LOCAL_TRAPS will be
     set as well, causing the effects of the emulate command and any
     setopt, disable -p or enable -p, and trap commands to be local to
     the immediately surrounding shell function, if any; normally these
     options are turned off in all emulation modes except ksh.  The -L
     switch is mutually exclusive with the use of -c in FLAGS.

     If there is a single argument and the -l switch is given, the
     options that would be set or unset (the latter indicated with the
     prefix 'no') are listed.  -l can be combined with -L or -R and the
     list will be modified in the appropriate way.  Note the list does
     not depend on the current setting of options, i.e.  it includes all
     options that may in principle change, not just those that would
     actually change.

     The FLAGS may be any of the invocation-time flags described in
     *note Invocation::, except that '-o EMACS' and '-o VI' may not be
     used.  Flags such as '+r'/'+o RESTRICTED' may be prohibited in some
     circumstances.

     If -c ARG appears in FLAGS, ARG is evaluated while the requested
     emulation is temporarily in effect.  In this case the emulation
     mode and all options are restored to their previous values before
     emulate returns.  The -R switch may precede the name of the shell
     to emulate; note this has a meaning distinct from including -R in
     FLAGS.

     Use of -c enables 'sticky' emulation mode for functions defined
     within the evaluated expression: the emulation mode is associated
     thereafter with the function so that whenever the function is
     executed the emulation (respecting the -R switch, if present) and
     all options are set (and pattern disables cleared) before entry to
     the function, and the state is restored after exit.  If the
     function is called when the sticky emulation is already in effect,
     either within an 'emulate SHELL -c' expression or within another
     function with the same sticky emulation, entry and exit from the
     function do not cause options to be altered (except due to standard
     processing such as the LOCAL_OPTIONS option).  This also applies to
     functions marked for autoload within the sticky emulation; the
     appropriate set of options will be applied at the point the
     function is loaded as well as when it is run.

     For example:

          emulate sh -c 'fni() { setopt cshnullglob; }
          fno() { fni; }'
          fno

     The two functions fni and fno are defined with sticky sh emulation.
     fno is then executed, causing options associated with emulations to
     be set to their values in sh.  fno then calls fni; because fni is
     also marked for sticky sh emulation, no option changes take place
     on entry to or exit from it.  Hence the option cshnullglob, turned
     off by sh emulation, will be turned on within fni and remain on
     return to fno.  On exit from fno, the emulation mode and all
     options will be restored to the state they were in before entry to
     the temporary emulation.

     The documentation above is typically sufficient for the intended
     purpose of executing code designed for other shells in a suitable
     environment.  More detailed rules follow.
     1.
          The sticky emulation environment provided by 'emulate SHELL
          -c' is identical to that provided by entry to a function
          marked for sticky emulation as a consequence of being defined
          in such an environment.  Hence, for example, the sticky
          emulation is inherited by subfunctions defined within
          functions with sticky emulation.
     2.
          No change of options takes place on entry to or exit from
          functions that are not marked for sticky emulation, other than
          those that would normally take place, even if those functions
          are called within sticky emulation.
     3.
          No special handling is provided for functions marked for
          autoload nor for functions present in wordcode created by the
          zcompile command.
     4.
          The presence or absence of the -R switch to emulate
          corresponds to different sticky emulation modes, so for
          example 'emulate sh -c', 'emulate -R sh -c' and 'emulate csh
          -c' are treated as three distinct sticky emulations.
     5.
          Difference in shell options supplied in addition to the basic
          emulation also mean the sticky emulations are different, so
          for example 'emulate zsh -c' and 'emulate zsh -o cbases -c'
          are treated as distinct sticky emulations.

enable [ -afmprs ] NAME ...
     Enable the NAMEd hash table elements, presumably disabled earlier
     with disable.  The default is to enable builtin commands.  The -a
     option causes enable to act on regular or global aliases.  The -s
     option causes enable to act on suffix aliases.  The -f option
     causes enable to act on shell functions.  The -r option causes
     enable to act on reserved words.  Without arguments all enabled
     hash table elements from the corresponding hash table are printed.
     With the -m flag the arguments are taken as patterns (should be
     quoted) and all hash table elements from the corresponding hash
     table matching these patterns are enabled.  Enabled objects can be
     disabled with the disable builtin command.

     enable -p reenables patterns disabled with disable -p.  Note that
     it does not override globbing options; for example, 'enable -p "~"'
     does not cause the pattern character ~ to be active unless the
     EXTENDED_GLOB option is also set.  To enable all possible patterns
     (so that they may be individually disabled with disable -p), use
     'setopt EXTENDED_GLOB KSH_GLOB NO_SH_GLOB'.

eval [ ARG ... ]
     Read the arguments as input to the shell and execute the resulting
     command(s) in the current shell process.  The return status is the
     same as if the commands had been executed directly by the shell; if
     there are no ARGS or they contain no commands (i.e.  are an empty
     string or whitespace) the return status is zero.

exec [ -cl ] [ -a ARGV0 ] [ COMMAND [ ARG ... ] ]
     Replace the current shell with COMMAND rather than forking.  If
     COMMAND is a shell builtin command or a shell function, the shell
     executes it, and exits when the command is complete.

     With -c clear the environment; with -l prepend - to the argv[0]
     string of the command executed (to simulate a login shell); with -a
     ARGV0 set the argv[0] string of the command executed.  See *note
     Precommand Modifiers::.

     If the option POSIX_BUILTINS is set, COMMAND is never interpreted
     as a shell builtin command or shell function.  This means further
     precommand modifiers such as builtin and noglob are also not
     interpreted within the shell.  Hence COMMAND is always found by
     searching the command path.

     If COMMAND is omitted but any redirections are specified, then the
     redirections will take effect in the current shell.

exit [ N ]
     Exit the shell with the exit status specified by an arithmetic
     expression N; if none is specified, use the exit status from the
     last command executed.  An EOF condition will also cause the shell
     to exit, unless the IGNORE_EOF option is set.

     See notes at the end of *note Signals:: for some possibly
     unexpected interactions of the exit command with jobs.

export [ NAME[=VALUE] ... ]
     The specified NAMEs are marked for automatic export to the
     environment of subsequently executed commands.  Equivalent to
     typeset -gx.  If a parameter specified does not already exist, it
     is created in the global scope.

false [ ARG ... ]
     Do nothing and return an exit status of 1.

fc [ -e ENAME ] [ -s ] [ -LI ] [ -m MATCH ] [ OLD=NEW ... ] [ FIRST [ LAST ] ]
fc -l [ -LI ] [ -nrdfEiD ] [ -t TIMEFMT ] [ -m MATCH ]
      [ OLD=NEW ... ] [ FIRST [ LAST ] ]
fc -p [ -a ] [ FILENAME [ HISTSIZE [ SAVEHISTSIZE ] ] ]
fc -P
fc -ARWI [ FILENAME ]
     The fc command controls the interactive history mechanism.  Note
     that reading and writing of history options is only performed if
     the shell is interactive.  Usually this is detected automatically,
     but it can be forced by setting the interactive option when
     starting the shell.

     The first two forms of this command select a range of events from
     FIRST to LAST from the history list.  The arguments FIRST and LAST
     may be specified as a number or as a string.  A negative number is
     used as an offset to the current history event number.  A string
     specifies the most recent event beginning with the given string.
     All substitutions OLD=NEW, if any, are then performed on the text
     of the events.

     The range of events selected by numbers can be narrowed further by
     the following flags.
     -I
          restricts to only internal events (not from $HISTFILE)
     -L
          restricts to only local events (not from other shells, see
          SHARE_HISTORY in *note Description of Options:: - note that
          $HISTFILE is considered local when read at startup)
     -m
          takes the first argument as a pattern (which should be quoted)
          and only the history events matching this pattern are
          considered

     If FIRST is not specified, it will be set to -1 (the most recent
     event), or to -16 if the -l flag is given.  If LAST is not
     specified, it will be set to FIRST, or to -1 if the -l flag is
     given.  However, if the current event has added entries to the
     history with 'print -s' or 'fc -R', then the default LAST for -l
     includes all new history entries since the current event began.

     When the -l flag is given, the resulting events are listed on
     standard output.  Otherwise the editor program specified by -e
     ENAME is invoked on a file containing these history events.  If -e
     is not given, the value of the parameter FCEDIT is used; if that is
     not set the value of the parameter EDITOR is used; if that is not
     set a builtin default, usually 'vi' is used.  If ENAME is '-', no
     editor is invoked.  When editing is complete, the edited command is
     executed.

     The flag '-s' is equivalent to '-e -'.  The flag -r reverses the
     order of the events and the flag -n suppresses event numbers when
     listing.

     Also when listing,
     -d
          prints timestamps for each event
     -f
          prints full time-date stamps in the US 'MM/DD/YY HH:MM' format
     -E
          prints full time-date stamps in the European 'DD.MM.YYYY
          HH:MM' format
     -i
          prints full time-date stamps in ISO8601 'YYYY-MM-DD HH:MM'
          format
     -t FMT
          prints time and date stamps in the given format; FMT is
          formatted with the strftime function with the zsh extensions
          described for the %D{STRING} prompt format in *note Simple
          Prompt Escapes::.  The resulting formatted string must be no
          more than 256 characters or will not be printed

     -D
          prints elapsed times; may be combined with one of the options
          above

     'fc -p' pushes the current history list onto a stack and switches
     to a new history list.  If the -a option is also specified, this
     history list will be automatically popped when the current function
     scope is exited, which is a much better solution than creating a
     trap function to call 'fc -P' manually.  If no arguments are
     specified, the history list is left empty, $HISTFILE is unset, and
     $HISTSIZE & $SAVEHIST are set to their default values.  If one
     argument is given, $HISTFILE is set to that filename, $HISTSIZE &
     $SAVEHIST are left unchanged, and the history file is read in (if
     it exists) to initialize the new list.  If a second argument is
     specified, $HISTSIZE & $SAVEHIST are instead set to the single
     specified numeric value.  Finally, if a third argument is
     specified, $SAVEHIST is set to a separate value from $HISTSIZE.
     You are free to change these environment values for the new history
     list however you desire in order to manipulate the new history
     list.

     'fc -P' pops the history list back to an older list saved by 'fc
     -p'.  The current list is saved to its $HISTFILE before it is
     destroyed (assuming that $HISTFILE and $SAVEHIST are set
     appropriately, of course).  The values of $HISTFILE, $HISTSIZE, and
     $SAVEHIST are restored to the values they had when 'fc -p' was
     called.  Note that this restoration can conflict with making these
     variables "local", so your best bet is to avoid local declarations
     for these variables in functions that use 'fc -p'.  The one other
     guaranteed-safe combination is declaring these variables to be
     local at the top of your function and using the automatic option
     (-a) with 'fc -p'.  Finally, note that it is legal to manually pop
     a push marked for automatic popping if you need to do so before the
     function exits.

     'fc -R' reads the history from the given file, 'fc -W' writes the
     history out to the given file, and 'fc -A' appends the history out
     to the given file.  If no filename is specified, the $HISTFILE is
     assumed.  If the -I option is added to -R, only those events that
     are not already contained within the internal history list are
     added.  If the -I option is added to -A or -W, only those events
     that are new since last incremental append/write to the history
     file are appended/written.  In any case, the created file will have
     no more than $SAVEHIST entries.

fg [ JOB ... ]
JOB ...
     Bring each specified JOB in turn to the foreground.  If no JOB is
     specified, resume the current job.

float [ {+|-}Hghlprtux ] [ {+|-}EFLRZ [ N ] ] [ NAME[=VALUE] ... ]
     Equivalent to typeset -E, except that options irrelevant to
     floating point numbers are not permitted.

functions [ {+|-}UkmtTuWz ] [ -x NUM ] [ NAME ... ]
functions -c OLDFN NEWFN
functions -M [-s] MATHFN [ MIN [ MAX [ SHELLFN ] ] ]
functions -M [ -m PATTERN ... ]
functions +M [ -m ] MATHFN ...
     Equivalent to typeset -f, with the exception of the -c, -x, -M and
     -W options.  For functions -u and functions -U, see autoload, which
     provides additional options.  For functions -t and functions -T,
     see typeset -f.

     The -x option indicates that any functions output will have each
     leading tab for indentation, added by the shell to show syntactic
     structure, expanded to the given number NUM of spaces.  NUM can
     also be 0 to suppress all indentation.

     The -W option turns on the option WARN_NESTED_VAR for the named
     function or functions only.  The option is turned off at the start
     of nested functions (apart from anonoymous functions) unless the
     called function also has the -W attribute.

     The -c option causes OLDFN to be copied to NEWFN.  The copy is
     efficiently handled internally by reference counting.  If OLDFN was
     marked for autoload it is first loaded and if this fails the copy
     fails.  Either function may subsequently be redefined without
     affecting the other.  A typical idiom is that OLDFN is the name of
     a library shell function which is then redefined to call newfn,
     thereby installing a modified version of the function.

     _The _-M_ and _+M_ flags_

     Use of the -M option may not be combined with any of the options
     handled by typeset -f.

     functions -M MATHFN defines MATHFN as the name of a mathematical
     function recognised in all forms of arithmetical expressions; see
     *note Arithmetic Evaluation::.  By default MATHFN may take any
     number of comma-separated arguments.  If MIN is given, it must have
     exactly MIN args; if MIN and MAX are both given, it must have at
     least MIN and at most MAX args.  MAX may be -1 to indicate that
     there is no upper limit.

     By default the function is implemented by a shell function of the
     same name; if SHELLFN is specified it gives the name of the
     corresponding shell function while MATHFN remains the name used in
     arithmetical expressions.  The name of the function in $0 is MATHFN
     (not SHELLFN as would usually be the case), provided the option
     FUNCTION_ARGZERO is in effect.  The positional parameters in the
     shell function correspond to the arguments of the mathematical
     function call.

     The result of the last arithmetical expression evaluated inside the
     shell function gives the result of the mathematical function.  This
     is not limited to arithmetic substitutions of the form $((...)),
     but also includes arithmetical expressions evaluated in any other
     way, including by the let builtin, by ((...)) statements, and even
     by the return builtin and by array subscripts.  Therefore, care
     must be taken not to use syntactical constructs that perform
     arithmetic evaluation after evaluating what is to be the result of
     the function.  For example:

          # WRONG
          zmath_cube() {
            (( $1 * $1 * $1 ))
            return 0
          }
          functions -M cube 1 1 zmath_cube
          print $(( cube(3) ))

     This will print '0' because of the return.

     Commenting the return out would lead to a different problem: the
     ((...)) statement would become the last statement in the function,
     so the _return status_ ($?) of the function would be non-zero
     (indicating failure) whenever the _arithmetic result_ of the
     function would happen to be zero (numerically):

          # WRONG
          zmath_cube() {
            (( $1 * $1 * $1 ))
          }
          functions -M cube 1 1 zmath_cube
          print $(( cube(0) ))

     Instead, the true builtin can be used:

          # RIGHT
          zmath_cube() {
            (( $1 * $1 * $1 ))
            true
          }
          functions -M cube 1 1 zmath_cube
          print $(( cube(3) ))

     If the additional option -s is given to functions -M, the argument
     to the function is a single string: anything between the opening
     and matching closing parenthesis is passed to the function as a
     single argument, even if it includes commas or white space.  The
     minimum and maximum argument specifiers must therefore be 1 if
     given.  An empty argument list is passed as a zero-length string.
     Thus, the following string function takes a single argument,
     including the commas, and prints 11:

          stringfn() { (( $#1 )); true }
          functions -Ms stringfn
          print $(( stringfn(foo,bar,rod) ))

     functions -M with no arguments lists all such user-defined
     functions in the same form as a definition.  With the additional
     option -m and a list of arguments, all functions whose MATHFN
     matches one of the pattern arguments are listed.

     function +M removes the list of mathematical functions; with the
     additional option -m the arguments are treated as patterns and all
     functions whose MATHFN matches the pattern are removed.  Note that
     the shell function implementing the behaviour is not removed
     (regardless of whether its name coincides with MATHFN).

getcap
     See *note The zsh/cap Module::.

getln [ -AclneE ] NAME ...
     Read the top value from the buffer stack and put it in the shell
     parameter NAME.  Equivalent to read -zr.

getopts OPTSTRING NAME [ ARG ... ]
     Checks the ARGs for legal options.  If the ARGs are omitted, use
     the positional parameters.  A valid option argument begins with a
     '+' or a '-'.  An argument not beginning with a '+' or a '-', or
     the argument '--', ends the options.  Note that a single '-' is not
     considered a valid option argument.  OPTSTRING contains the letters
     that getopts recognizes.  If a letter is followed by a ':', that
     option requires an argument.  The options can be separated from the
     argument by blanks.

     Each time it is invoked, getopts places the option letter it finds
     in the shell parameter NAME, prepended with a '+' when ARG begins
     with a '+'.  The index of the next ARG is stored in OPTIND.  The
     option argument, if any, is stored in OPTARG.

     The first option to be examined may be changed by explicitly
     assigning to OPTIND.  OPTIND has an initial value of 1, and is
     normally set to 1 upon entry to a shell function and restored upon
     exit.  (The POSIX_BUILTINS option disables this, and also changes
     the way the value is calculated to match other shells.)  OPTARG is
     not reset and retains its value from the most recent call to
     getopts.  If either of OPTIND or OPTARG is explicitly unset, it
     remains unset, and the index or option argument is not stored.  The
     option itself is still stored in NAME in this case.

     A leading ':' in OPTSTRING causes getopts to store the letter of
     any invalid option in OPTARG, and to set NAME to '?' for an unknown
     option and to ':' when a required argument is missing.  Otherwise,
     getopts sets NAME to '?' and prints an error message when an option
     is invalid.  The exit status is nonzero when there are no more
     options.

hash [ -Ldfmrv ] [ NAME[=VALUE] ] ...
     hash can be used to directly modify the contents of the command
     hash table, and the named directory hash table.  Normally one would
     modify these tables by modifying one's PATH (for the command hash
     table) or by creating appropriate shell parameters (for the named
     directory hash table).  The choice of hash table to work on is
     determined by the -d option; without the option the command hash
     table is used, and with the option the named directory hash table
     is used.

     A command NAME starting with a / or with a relative path starting
     with ./ or ../ is never executed by lookup in the command hash
     table, and these can only be added to the table by explicit use of
     the hash command.  Such a command is always found by direct look up
     in the file system.

     Given no arguments, and neither the -r or -f options, the selected
     hash table will be listed in full.

     The -r option causes the selected hash table to be emptied.  It
     will be subsequently rebuilt in the normal fashion.  The -f option
     causes the selected hash table to be fully rebuilt immediately.
     For the command hash table this hashes all (and _only_) the
     absolute directories in the PATH, and for the named directory hash
     table this adds all users' home directories.  These two options
     cannot be used with any arguments.  Both options remove any
     explicitly-added elements.

     The -m option causes the arguments to be taken as patterns (which
     should be quoted) and the elements of the hash table matching those
     patterns are printed.  This is the only way to display a limited
     selection of hash table elements.

     For each NAME with a corresponding VALUE, put 'NAME' in the
     selected hash table, associating it with the pathname 'VALUE'.  In
     the command hash table, this means that whenever 'NAME' is used as
     a command argument, the shell will try to execute the file given by
     'VALUE'.  In the named directory hash table, this means that
     'VALUE' may be referred to as '~NAME'.

     For each NAME with no corresponding VALUE, attempt to add NAME to
     the hash table, checking what the appropriate value is in the
     normal manner for that hash table.  If an appropriate value can't
     be found, then the hash table will be unchanged.

     The -v option causes hash table entries to be listed as they are
     added by explicit specification.  If has no effect if used with -f.

     If the -L flag is present, then each hash table entry is printed in
     the form of a call to hash.

history
     Same as fc -l.

integer [ {+|-}Hghlprtux ] [ {+|-}LRZi [ N ] ] [ NAME[=VALUE] ... ]
     Equivalent to typeset -i, except that options irrelevant to
     integers are not permitted.

jobs [ -dlprs ] [ JOB ... ]
jobs -Z STRING
     Lists information about each given job, or all jobs if JOB is
     omitted.  The -l flag lists process IDs, and the -p flag lists
     process groups.  If the -r flag is specified only running jobs will
     be listed and if the -s flag is given only stopped jobs are shown.
     If the -d flag is given, the directory from which the job was
     started (which may not be the current directory of the job) will
     also be shown.

     The -Z option replaces the shell's argument and environment space
     with the given string, truncated if necessary to fit.  This will
     normally be visible in ps (ps(1)) listings.  This feature is
     typically used by daemons, to indicate their state.

     Full job control is only available in the top-level interactive
     shell, not in commands run in the left hand side of pipelines or
     within the (...) construct.  However, a snapshot of the job state
     at that point is taken, so it is still possible to use the jobs
     builtin, or any parameter providing job information.  This gives
     information about the state of jobs at the point the subshell was
     created.  If background processes are created within the subshell,
     then instead information about those processes is provided.

     For example,

          sleep 10 &    # Job in background
          (             # Shell forks
          jobs          # Shows information about "sleep 10 &"
          sleep 5 &     # Process in background (no job control)
          jobs          # Shows information about "sleep 5 &"
          )

kill [ -s SIGNAL_NAME | -n SIGNAL_NUMBER | -SIG ] [ -q VALUE ] JOB ...
kill -l [ SIG ... ]
kill -L
     Sends either SIGTERM or the specified signal to the given jobs or
     processes.  Signals are given by number or by names, with or
     without the 'SIG' prefix.  If the signal being sent is not 'KILL'
     or 'CONT', then the job will be sent a 'CONT' signal if it is
     stopped.  The argument JOB can be the process ID of a job not in
     the job list.  In the second form, kill -l, if SIG is not specified
     the signal names are listed.  Otherwise, for each SIG that is a
     name, the corresponding signal number is listed.  For each SIG that
     is a signal number or a number representing the exit status of a
     process which was terminated or stopped by a signal the name of the
     signal is printed.  The final form with -L lists each signal name
     with its corresponding number.

     On some systems, alternative signal names are allowed for a few
     signals.  Typical examples are SIGCHLD and SIGCLD or SIGPOLL and
     SIGIO, assuming they correspond to the same signal number.  kill -l
     will only list the preferred form, however kill -l ALT will show if
     the alternative form corresponds to a signal number.  For example,
     under Linux kill -l IO and kill -l POLL both output 29, hence kill
     -IO and kill -POLL have the same effect.

     Many systems will allow process IDs to be negative to kill a
     process group or zero to kill the current process group.

     The -q option allows an integer value to be sent with the signal on
     systems that support sigqueue().

let ARG ...
     Evaluate each ARG as an arithmetic expression.  See *note
     Arithmetic Evaluation:: for a description of arithmetic
     expressions.  The exit status is 0 if the value of the last
     expression is nonzero, 1 if it is zero, and 2 if an error occurred.

limit [ -hs ] [ RESOURCE [ LIMIT ] ] ...
     Set or display resource limits.  Unless the -s flag is given, the
     limit applies only the children of the shell.  If -s is given
     without other arguments, the resource limits of the current shell
     is set to the previously set resource limits of the children.

     If LIMIT is not specified, print the current limit placed on
     RESOURCE, otherwise set the limit to the specified value.  If the
     -h flag is given, use hard limits instead of soft limits.  If no
     RESOURCE is given, print all limits.

     When looping over multiple resources, the shell will abort
     immediately if it detects a badly formed argument.  However, if it
     fails to set a limit for some other reason it will continue trying
     to set the remaining limits.

     RESOURCE can be one of:

     addressspace
          Maximum amount of address space used.
     aiomemorylocked
          Maximum amount of memory locked in RAM for AIO operations.
     aiooperations
          Maximum number of AIO operations.
     cachedthreads
          Maximum number of cached threads.
     coredumpsize
          Maximum size of a core dump.
     cputime
          Maximum CPU seconds per process.
     datasize
          Maximum data size (including stack) for each process.
     descriptors
          Maximum value for a file descriptor.
     filesize
          Largest single file allowed.
     kqueues
          Maximum number of kqueues allocated.
     maxfilelocks
          Maximum number of file locks.
     maxproc
          Maximum number of processes.
     maxpthreads
          Maximum number of threads per process.
     memorylocked
          Maximum amount of memory locked in RAM.
     memoryuse
          Maximum resident set size.
     msgqueue
          Maximum number of bytes in POSIX message queues.
     nice
          Maximum nice value.
     pipebuf
          Maximum size of buffers for pipes/fifos.
     posixlocks
          Maximum number of POSIX locks per user.
     pseudoterminals
          Maximum number of pseudo-terminals.
     resident
          Maximum resident set size.
     rt_priority
          Maximum real-time priority.
     rt_time
          Maximum CPU time without a blocking system call.
     sigpending
          Maximum number of pending signals.
     sockbufsize
          Maximum size of all socket buffers.
     stacksize
          Maximum stack size for each process.
     swapsize
          Maximum amount of swap used.
     umtxp
          Maximum number of POSIX thread library objects.
     vmemorysize
          Maximum amount of virtual memory.
     vnodemonitors
          Maximum number of open vnode monitors.

     Which of these resource limits are available depends on the system.
     RESOURCE can be abbreviated to any unambiguous prefix.  It can also
     be an integer, which corresponds to the integer defined for the
     resource by the operating system.

     If argument corresponds to a number which is out of the range of
     the resources configured into the shell, the shell will try to read
     or write the limit anyway, and will report an error if this fails.
     As the shell does not store such resources internally, an attempt
     to set the limit will fail unless the -s option is present.

     LIMIT is a number, with an optional scaling factor, as follows:

     Nh
          hours
     Nk
          kilobytes (default)
     Nm
          megabytes or minutes
     Ng
          gigabytes
     [MM:]SS
          minutes and seconds

     The limit command is not made available by default when the shell
     starts in a mode emulating another shell.  It can be made available
     with the command 'zmodload -F zsh/rlimits b:limit'.

local [ {+|-}AHUahlprtux ] [ {+|-}EFLRZi [ N ] ] [ NAME[=VALUE] ... ]
     Same as typeset, except that the options -g, and -f are not
     permitted.  In this case the -x option does not force the use of
     -g, i.e.  exported variables will be local to functions.

logout [ N ]
     Same as exit, except that it only works in a login shell.

noglob SIMPLE COMMAND
     See *note Precommand Modifiers::.

popd [ -q ] [ {+|-}N ]
     Remove an entry from the directory stack, and perform a cd to the
     new top directory.  With no argument, the current top entry is
     removed.  An argument of the form '+N' identifies a stack entry by
     counting from the left of the list shown by the dirs command,
     starting with zero.  An argument of the form -N counts from the
     right.  If the PUSHD_MINUS option is set, the meanings of '+' and
     '-' in this context are swapped.

     If the -q (quiet) option is specified, the hook function chpwd and
     the functions in the array $chpwd_functions are not called, and the
     new directory stack is not printed.  This is useful for calls to
     popd that do not change the environment seen by an interactive
     user.

print [ -abcDilmnNoOpPrsSz ] [ -u N ] [ -f FORMAT ] [ -C COLS ]
      [ -v NAME ] [ -xX TABSTOP ] [ -R [ -en ]] [ ARG ... ]
     With the '-f' option the arguments are printed as described by
     printf.  With no flags or with the flag '-', the arguments are
     printed on the standard output as described by echo, with the
     following differences: the escape sequence '\M-X' (or '\MX')
     metafies the character X (sets the highest bit), '\C-X' (or '\CX')
     produces a control character ('\C-@' and '\C-?' give the characters
     NULL and delete), a character code in octal is represented by
     '\NNN' (instead of '\0NNN'), and '\E' is a synonym for '\e'.
     Finally, if not in an escape sequence, '\' escapes the following
     character and is not printed.

     -a
          Print arguments with the column incrementing first.  Only
          useful with the -c and -C options.

     -b
          Recognize all the escape sequences defined for the bindkey
          command, see *note Zle Builtins::.

     -c
          Print the arguments in columns.  Unless -a is also given,
          arguments are printed with the row incrementing first.

     -C COLS
          Print the arguments in COLS columns.  Unless -a is also given,
          arguments are printed with the row incrementing first.

     -D
          Treat the arguments as paths, replacing directory prefixes
          with ~ expressions corresponding to directory names, as
          appropriate.

     -i
          If given together with -o or -O, sorting is performed
          case-independently.

     -l
          Print the arguments separated by newlines instead of spaces.
          Note: if the list of arguments is empty, print -l will still
          output one empty line.  To print a possibly-empty list of
          arguments one per line, use print -C1, as in 'print -rC1 --
          "$list[@]"'.

     -m
          Take the first argument as a pattern (should be quoted), and
          remove it from the argument list together with subsequent
          arguments that do not match this pattern.

     -n
          Do not add a newline to the output.

     -N
          Print the arguments separated and terminated by nulls.  Again,
          print -rNC1 -- "$list[@]" is a canonical way to print an
          arbitrary list as null-delimited records.

     -o
          Print the arguments sorted in ascending order.

     -O
          Print the arguments sorted in descending order.

     -p
          Print the arguments to the input of the coprocess.

     -P
          Perform prompt expansion (see *note Expansion of Prompt
          Sequences::).  In combination with '-f', prompt escape
          sequences are parsed only within interpolated arguments, not
          within the format string.

     -r
          Ignore the escape conventions of echo.

     -R
          Emulate the BSD echo command, which does not process escape
          sequences unless the -e flag is given.  The -n flag suppresses
          the trailing newline.  Only the -e and -n flags are recognized
          after -R; all other arguments and options are printed.

     -s
          Place the results in the history list instead of on the
          standard output.  Each argument to the print command is
          treated as a single word in the history, regardless of its
          content.

     -S
          Place the results in the history list instead of on the
          standard output.  In this case only a single argument is
          allowed; it will be split into words as if it were a full
          shell command line.  The effect is similar to reading the line
          from a history file with the HIST_LEX_WORDS option active.

     -u N
          Print the arguments to file descriptor N.

     -v NAME
          Store the printed arguments as the value of the parameter
          NAME.

     -x TAB-STOP
          Expand leading tabs on each line of output in the printed
          string assuming a tab stop every TAB-STOP characters.  This is
          appropriate for formatting code that may be indented with
          tabs.  Note that leading tabs of any argument to print, not
          just the first, are expanded, even if print is using spaces to
          separate arguments (the column count is maintained across
          arguments but may be incorrect on output owing to previous
          unexpanded tabs).

          The start of the output of each print command is assumed to be
          aligned with a tab stop.  Widths of multibyte characters are
          handled if the option MULTIBYTE is in effect.  This option is
          ignored if other formatting options are in effect, namely
          column alignment or printf style, or if output is to a special
          location such as shell history or the command line editor.

     -X TAB-STOP
          This is similar to -x, except that all tabs in the printed
          string are expanded.  This is appropriate if tabs in the
          arguments are being used to produce a table format.

     -z
          Push the arguments onto the editing buffer stack, separated by
          spaces.

     If any of '-m', '-o' or '-O' are used in combination with '-f' and
     there are no arguments (after the removal process in the case of
     '-m') then nothing is printed.

printf [ -v NAME ] FORMAT [ ARG ... ]
     Print the arguments according to the format specification.
     Formatting rules are the same as used in C. The same escape
     sequences as for echo are recognised in the format.  All C
     conversion specifications ending in one of csdiouxXeEfgGn are
     handled.  In addition to this, '%b' can be used instead of '%s' to
     cause escape sequences in the argument to be recognised and '%q'
     can be used to quote the argument in such a way that allows it to
     be reused as shell input.  With the numeric format specifiers, if
     the corresponding argument starts with a quote character, the
     numeric value of the following character is used as the number to
     print; otherwise the argument is evaluated as an arithmetic
     expression.  See *note Arithmetic Evaluation:: for a description of
     arithmetic expressions.  With '%n', the corresponding argument is
     taken as an identifier which is created as an integer parameter.

     Normally, conversion specifications are applied to each argument in
     order but they can explicitly specify the Nth argument is to be
     used by replacing '%' by '%N$' and '*' by '*N$'.  It is recommended
     that you do not mix references of this explicit style with the
     normal style and the handling of such mixed styles may be subject
     to future change.

     If arguments remain unused after formatting, the format string is
     reused until all arguments have been consumed.  With the print
     builtin, this can be suppressed by using the -r option.  If more
     arguments are required by the format than have been specified, the
     behaviour is as if zero or an empty string had been specified as
     the argument.

     The -v option causes the output to be stored as the value of the
     parameter NAME, instead of printed.  If NAME is an array and the
     format string is reused when consuming arguments then one array
     element will be used for each use of the format string.

pushd [ -qsLP ] [ ARG ]
pushd [ -qsLP ] OLD NEW
pushd [ -qsLP ] {+|-}N
     Change the current directory, and push the old current directory
     onto the directory stack.  In the first form, change the current
     directory to ARG.  If ARG is not specified, change to the second
     directory on the stack (that is, exchange the top two entries), or
     change to $HOME if the PUSHD_TO_HOME option is set or if there is
     only one entry on the stack.  Otherwise, ARG is interpreted as it
     would be by cd.  The meaning of OLD and NEW in the second form is
     also the same as for cd.

     The third form of pushd changes directory by rotating the directory
     list.  An argument of the form '+N' identifies a stack entry by
     counting from the left of the list shown by the dirs command,
     starting with zero.  An argument of the form '-N' counts from the
     right.  If the PUSHD_MINUS option is set, the meanings of '+' and
     '-' in this context are swapped.

     If the -q (quiet) option is specified, the hook function chpwd and
     the functions in the array $chpwd_functions are not called, and the
     new directory stack is not printed.  This is useful for calls to
     pushd that do not change the environment seen by an interactive
     user.

     If the option -q is not specified and the shell option PUSHD_SILENT
     is not set, the directory stack will be printed after a pushd is
     performed.

     The options -s, -L and -P have the same meanings as for the cd
     builtin.

pushln [ ARG ... ]
     Equivalent to print -nz.

pwd [ -rLP ]
     Print the absolute pathname of the current working directory.  If
     the -r or the -P flag is specified, or the CHASE_LINKS option is
     set and the -L flag is not given, the printed path will not contain
     symbolic links.

r
     Same as fc -e -.

read [ -rszpqAclneE ] [ -t [ NUM ] ] [ -k [ NUM ] ] [ -d DELIM ]
     [ -u N ] [ [NAME][?PROMPT] ] [ NAME ... ]
     Read one line and break it into fields using the characters in $IFS
     as separators, except as noted below.  The first field is assigned
     to the first NAME, the second field to the second NAME, etc., with
     leftover fields assigned to the last NAME.  If NAME is omitted then
     REPLY is used for scalars and reply for arrays.

     -r
          Raw mode: a '\' at the end of a line does not signify line
          continuation and backslashes in the line don't quote the
          following character and are not removed.

     -s
          Don't echo back characters if reading from the terminal.

     -q
          Read only one character from the terminal and set NAME to 'y'
          if this character was 'y' or 'Y' and to 'n' otherwise.  With
          this flag set the return status is zero only if the character
          was 'y' or 'Y'.  This option may be used with a timeout (see
          -t); if the read times out, or encounters end of file, status
          2 is returned.  Input is read from the terminal unless one of
          -u or -p is present.  This option may also be used within zle
          widgets.

     -k [ NUM ]
          Read only one (or NUM) characters.  All are assigned to the
          first NAME, without word splitting.  This flag is ignored when
          -q is present.  Input is read from the terminal unless one of
          -u or -p is present.  This option may also be used within zle
          widgets.

          Note that despite the mnemonic 'key' this option does read
          full characters, which may consist of multiple bytes if the
          option MULTIBYTE is set.

     -z
          Read one entry from the editor buffer stack and assign it to
          the first NAME, without word splitting.  Text is pushed onto
          the stack with 'print -z' or with push-line from the line
          editor (see *note Zsh Line Editor::).  This flag is ignored
          when the -k or -q flags are present.

     -e
     -E
          The input read is printed (echoed) to the standard output.  If
          the -e flag is used, no input is assigned to the parameters.

     -A
          The first NAME is taken as the name of an array and all words
          are assigned to it.

     -c
     -l
          These flags are allowed only if called inside a function used
          for completion (specified with the -K flag to compctl).  If
          the -c flag is given, the words of the current command are
          read.  If the -l flag is given, the whole line is assigned as
          a scalar.  If both flags are present, -l is used and -c is
          ignored.

     -n
          Together with -c, the number of the word the cursor is on is
          read.  With -l, the index of the character the cursor is on is
          read.  Note that the command name is word number 1, not word
          0, and that when the cursor is at the end of the line, its
          character index is the length of the line plus one.

     -u N
          Input is read from file descriptor N.

     -p
          Input is read from the coprocess.

     -d DELIM
          Input is terminated by the first character of DELIM instead of
          by newline.  For compatibility with other shells, if DELIM is
          an empty string, input is terminated at the first NUL.

     -t [ NUM ]
          Test if input is available before attempting to read.  If NUM
          is present, it must begin with a digit and will be evaluated
          to give a number of seconds, which may be a floating point
          number; in this case the read times out if input is not
          available within this time.  If NUM is not present, it is
          taken to be zero, so that read returns immediately if no input
          is available.  If no input is available, return status 1 and
          do not set any variables.

          This option is not available when reading from the editor
          buffer with -z, when called from within completion with -c or
          -l, with -q which clears the input queue before reading, or
          within zle where other mechanisms should be used to test for
          input.

          Note that read does not attempt to alter the input processing
          mode.  The default mode is canonical input, in which an entire
          line is read at a time, so usually 'read -t' will not read
          anything until an entire line has been typed.  However, when
          reading from the terminal with -k input is processed one key
          at a time; in this case, only availability of the first
          character is tested, so that e.g.  'read -t -k 2' can still
          block on the second character.  Use two instances of 'read -t
          -k' if this is not what is wanted.

     If the first argument contains a '?', the remainder of this word is
     used as a PROMPT on standard error when the shell is interactive.

     The value (exit status) of read is 1 when an end-of-file is
     encountered, or when -c or -l is present and the command is not
     called from a compctl function, or as described for -q.  Otherwise
     the value is 0.

     The behavior of some combinations of the -k, -p, -q, -u and -z
     flags is undefined.  Presently -q cancels all the others, -p
     cancels -u, -k cancels -z, and otherwise -z cancels both -p and -u.

     The -c or -l flags cancel any and all of -kpquz.

readonly
     Same as typeset -r.  With the POSIX_BUILTINS option set, same as
     typeset -gr.

rehash
     Same as hash -r.

return [ N ]
     Causes a shell function or '.' script to return to the invoking
     script with the return status specified by an arithmetic expression
     N.  Also causes a non-interctive shell to exit, allowing files
     containing shell code to be used both as scripts and as
     autoloadable shell functions.  For example, the following prints
     '42':

          () { integer foo=40; return "foo + 2" }
          echo $?

     If N is omitted, the return status is that of the last command
     executed.

     If return was executed from a trap in a TRAPNAL function, the
     effect is different for zero and non-zero return status.  With zero
     status (or after an implicit return at the end of the trap), the
     shell will return to whatever it was previously processing; with a
     non-zero status, the shell will behave as interrupted except that
     the return status of the trap is retained.  Note that the numeric
     value of the signal which caused the trap is passed as the first
     argument, so the statement 'return "128+$1"' will return the same
     status as if the signal had not been trapped.

sched
     See *note The zsh/sched Module::.

set [ {+|-}OPTIONS | {+|-}o [ OPTION_NAME ] ] ... [ {+|-}A [ NAME ] ]
    [ ARG ... ]
     Set the options for the shell and/or set the positional parameters,
     or declare and set an array.  If the -s option is given, it causes
     the specified arguments to be sorted before assigning them to the
     positional parameters (or to the array NAME if -A is used).  With
     +s sort arguments in descending order.  For the meaning of the
     other flags, see *note Options::.  Flags may be specified by name
     using the -o option.  If no option name is supplied with -o, the
     current option states are printed: see the description of setopt
     below for more information on the format.  With +o they are printed
     in a form that can be used as input to the shell.

     If the -A flag is specified, NAME is set to an array containing the
     given ARGs; if no NAME is specified, all arrays are printed
     together with their values.

     If +A is used and NAME is an array, the given arguments will
     replace the initial elements of that array; if no NAME is
     specified, all arrays are printed without their values.

     The behaviour of arguments after -A NAME or +A NAME depends on
     whether the option KSH_ARRAYS is set.  If it is not set, all
     arguments following NAME are treated as values for the array,
     regardless of their form.  If the option is set, normal option
     processing continues at that point; only regular arguments are
     treated as values for the array.  This means that

          set -A array -x -- foo

     sets array to '-x -- foo' if KSH_ARRAYS is not set, but sets the
     array to foo and turns on the option '-x' if it is set.

     If the -A flag is not present, but there are arguments beyond the
     options, the positional parameters are set.  If the option list (if
     any) is terminated by '--', and there are no further arguments, the
     positional parameters will be unset.

     If no arguments and no '--' are given, then the names and values of
     all parameters are printed on the standard output.  If the only
     argument is '+', the names of all parameters are printed.

     For historical reasons, 'set -' is treated as 'set +xv' and 'set -
     ARGS' as 'set +xv -- ARGS' when in any other emulation mode than
     zsh's native mode.

setcap
     See *note The zsh/cap Module::.

setopt [ {+|-}OPTIONS | {+|-}o OPTION_NAME ] [ -m ] [ NAME ... ]
     Set the options for the shell.  All options specified either with
     flags or by name are set.

     If no arguments are supplied, the names of all options currently
     set are printed.  The form is chosen so as to minimize the
     differences from the default options for the current emulation (the
     default emulation being native zsh, shown as <Z> in *note
     Description of Options::).  Options that are on by default for the
     emulation are shown with the prefix no only if they are off, while
     other options are shown without the prefix no and only if they are
     on.  In addition to options changed from the default state by the
     user, any options activated automatically by the shell (for
     example, SHIN_STDIN or INTERACTIVE) will be shown in the list.  The
     format is further modified by the option KSH_OPTION_PRINT, however
     the rationale for choosing options with or without the no prefix
     remains the same in this case.

     If the -m flag is given the arguments are taken as patterns (which
     should be quoted to protect them from filename expansion), and all
     options with names matching these patterns are set.

     Note that a bad option name does not cause execution of subsequent
     shell code to be aborted; this is behaviour is different from that
     of 'set -o'.  This is because set is regarded as a special builtin
     by the POSIX standard, but setopt is not.

shift [ -p ] [ N ] [ NAME ... ]
     The positional parameters ${N+1} ...  are renamed to $1 ..., where
     N is an arithmetic expression that defaults to 1.  If any NAMEs are
     given then the arrays with these names are shifted instead of the
     positional parameters.

     If the option -p is given arguments are instead removed (popped)
     from the end rather than the start of the array.

source FILE [ ARG ... ]
     Same as '.', except that the current directory is always searched
     and is always searched first, before directories in $path.

stat
     See *note The zsh/stat Module::.

suspend [ -f ]
     Suspend the execution of the shell (send it a SIGTSTP) until it
     receives a SIGCONT.  Unless the -f option is given, this will
     refuse to suspend a login shell.

test [ ARG ... ]
[ [ ARG ... ] ]
     Like the system version of test.  Added for compatibility; use
     conditional expressions instead (see *note Conditional
     Expressions::).  The main differences between the conditional
     expression syntax and the test and [ builtins are: these commands
     are not handled syntactically, so for example an empty variable
     expansion may cause an argument to be omitted; syntax errors cause
     status 2 to be returned instead of a shell error; and arithmetic
     operators expect integer arguments rather than arithmetic
     expressions.

     The command attempts to implement POSIX and its extensions where
     these are specified.  Unfortunately there are intrinsic ambiguities
     in the syntax; in particular there is no distinction between test
     operators and strings that resemble them.  The standard attempts to
     resolve these for small numbers of arguments (up to four); for five
     or more arguments compatibility cannot be relied on.  Users are
     urged wherever possible to use the '[[' test syntax which does not
     have these ambiguities.

times
     Print the accumulated user and system times for the shell and for
     processes run from the shell.

trap [ ARG ] [ SIG ... ]
     ARG is a series of commands (usually quoted to protect it from
     immediate evaluation by the shell) to be read and executed when the
     shell receives any of the signals specified by one or more SIG
     args.  Each SIG can be given as a number, or as the name of a
     signal either with or without the string SIG in front (e.g.  1,
     HUP, and SIGHUP are all the same signal).

     If ARG is '-', then the specified signals are reset to their
     defaults, or, if no SIG args are present, all traps are reset.

     If ARG is an empty string, then the specified signals are ignored
     by the shell (and by the commands it invokes).

     If ARG is omitted but one or more SIG args are provided (i.e.  the
     first argument is a valid signal number or name), the effect is the
     same as if ARG had been specified as '-'.

     The trap command with no arguments prints a list of commands
     associated with each signal.

     If SIG is ZERR then ARG will be executed after each command with a
     nonzero exit status.  ERR is an alias for ZERR on systems that have
     no SIGERR signal (this is the usual case).

     If SIG is DEBUG then ARG will be executed before each command if
     the option DEBUG_BEFORE_CMD is set (as it is by default), else
     after each command.  Here, a 'command' is what is described as a
     'sublist' in the shell grammar, see *note Simple Commands &
     Pipelines::.  If DEBUG_BEFORE_CMD is set various additional
     features are available.  First, it is possible to skip the next
     command by setting the option ERR_EXIT; see the description of the
     ERR_EXIT option in *note Description of Options::.  Also, the shell
     parameter ZSH_DEBUG_CMD is set to the string corresponding to the
     command to be executed following the trap.  Note that this string
     is reconstructed from the internal format and may not be formatted
     the same way as the original text.  The parameter is unset after
     the trap is executed.

     If SIG is 0 or EXIT and the trap statement is executed inside the
     body of a function, then the command ARG is executed after the
     function completes.  The value of $? at the start of execution is
     the exit status of the shell or the return status of the function
     exiting.  If SIG is 0 or EXIT and the trap statement is not
     executed inside the body of a function, then the command ARG is
     executed when the shell terminates; the trap runs before any
     zshexit hook functions.

     ZERR, DEBUG, and EXIT traps are not executed inside other traps.
     ZERR and DEBUG traps are kept within subshells, while other traps
     are reset.

     Note that traps defined with the trap builtin are slightly
     different from those defined as 'TRAPNAL () { ...  }', as the
     latter have their own function environment (line numbers, local
     variables, etc.)  while the former use the environment of the
     command in which they were called.  For example,

          trap 'print $LINENO' DEBUG

     will print the line number of a command executed after it has run,
     while

          TRAPDEBUG() { print $LINENO; }

     will always print the number zero.

     Alternative signal names are allowed as described under kill above.
     Defining a trap under either name causes any trap under an
     alternative name to be removed.  However, it is recommended that
     for consistency users stick exclusively to one name or another.

true [ ARG ... ]
     Do nothing and return an exit status of 0.

ttyctl [ -fu ]
     The -f option freezes the tty (i.e.  terminal or terminal
     emulator), and -u unfreezes it.  When the tty is frozen, no changes
     made to the tty settings by external programs will be honored by
     the shell, except for changes in the size of the screen; the shell
     will simply reset the settings to their previous values as soon as
     each command exits or is suspended.  Thus, stty and similar
     programs have no effect when the tty is frozen.  Freezing the tty
     does not cause the current state to be remembered: instead, it
     causes future changes to the state to be blocked.

     Without options it reports whether the terminal is frozen or not.

     Note that, regardless of whether the tty is frozen or not, the
     shell needs to change the settings when the line editor starts, so
     unfreezing the tty does not guarantee settings made on the command
     line are preserved.  Strings of commands run between editing the
     command line will see a consistent tty state.  See also the shell
     variable STTY for a means of initialising the tty before running
     external commands and/or freezing the tty around a single command.

type [ -wfpamsS ] NAME ...
     Equivalent to whence -v.

typeset [ {+|-}AHUaghlmrtux ] [ {+|-}EFLRZip [ N ] ]
        [ + ] [ NAME[=VALUE] ... ]
typeset {+|-}n [ -g ] [ {+|-}r ] [ NAME[=VALUE] ... ]
typeset -T [ {+|-}Uglrux ] [ {+|-}LRZp [ N ] ]
        [ + | SCALAR[=VALUE] ARRAY[=(VALUE ...)] [ SEP ] ]
typeset -f [ {+|-}TUkmtuz ] [ + ] [ NAME ... ]
     Set or display attributes and values for shell parameters.

     Except as noted below for control flags that change the behavior, a
     parameter is created for each NAME that does not already refer to
     one.  When inside a function, a new parameter is created for every
     NAME (even those that already exist), and is unset again when the
     function completes.  See *note Local Parameters::.  The same rules
     apply to special shell parameters, which retain their special
     attributes when made local.

     For each NAME=VALUE assignment, the parameter NAME is set to VALUE.
     If the assignment is omitted and NAME does _not_ refer to an
     existing parameter, a new parameter is initialized to empty string,
     zero, or empty array (as appropriate), _unless_ the shell option
     TYPESET_TO_UNSET is set.  When that option is set, the parameter
     attributes are recorded but the parameter remains unset.

     If the shell option TYPESET_SILENT is not set, for each remaining
     NAME that refers to a parameter that is already set, the name and
     value of the parameter are printed in the form of an assignment.
     Nothing is printed for newly-created parameters, or when any
     attribute flags listed below are given along with the NAME.  Using
     '+' instead of minus to introduce an attribute turns it off.

     If no NAME is present, the names and values of all parameters are
     printed.  In this case the attribute flags restrict the display to
     only those parameters that have the specified attributes, and using
     '+' rather than '-' to introduce the flag suppresses printing of
     the values of parameters when there is no parameter name.

     All forms of the command handle scalar assignment.  Array
     assignment is possible if any of the reserved words declare,
     export, float, integer, local, readonly or typeset is matched when
     the line is parsed (N.B. not when it is executed).  In this case
     the arguments are parsed as assignments, except that the '+='
     syntax and the GLOB_ASSIGN option are not supported, and scalar
     values after = are _not_ split further into words, even if expanded
     (regardless of the setting of the KSH_TYPESET option; this option
     is obsolete).

     Examples of the differences between command and reserved word
     parsing:

          # Reserved word parsing
          typeset svar=$(echo one word) avar=(several words)

     The above creates a scalar parameter svar and an array parameter
     avar as if the assignments had been

          svar="one word"
          avar=(several words)

     On the other hand:

          # Normal builtin interface
          builtin typeset svar=$(echo two words)

     The builtin keyword causes the above to use the standard builtin
     interface to typeset in which argument parsing is performed in the
     same way as for other commands.  This example creates a scalar svar
     containing the value two and another scalar parameter words with no
     value.  An array value in this case would either cause an error or
     be treated as an obscure set of glob qualifiers.

     Arbitrary arguments are allowed if they take the form of
     assignments after command line expansion; however, these only
     perform scalar assignment:

          var='svar=val'
          typeset $var

     The above sets the scalar parameter svar to the value val.
     Parentheses around the value within var would not cause array
     assignment as they will be treated as ordinary characters when $var
     is substituted.  Any non-trivial expansion in the name part of the
     assignment causes the argument to be treated in this fashion:

          typeset {var1,var2,var3}=name

     The above syntax is valid, and has the expected effect of setting
     the three parameters to the same value, but the command line is
     parsed as a set of three normal command line arguments to typeset
     after expansion.  Hence it is not possible to assign to multiple
     arrays by this means.

     Note that each interface to any of the commands may be disabled
     separately.  For example, 'disable -r typeset' disables the
     reserved word interface to typeset, exposing the builtin interface,
     while 'disable typeset' disables the builtin.  Note that disabling
     the reserved word interface for typeset may cause problems with the
     output of 'typeset -p', which assumes the reserved word interface
     is available in order to restore array and associative array
     values.

     Unlike parameter assignment statements, typeset's exit status on an
     assignment that involves a command substitution does not reflect
     the exit status of the command substitution.  Therefore, to test
     for an error in a command substitution, separate the declaration of
     the parameter from its initialization:

          # WRONG
          typeset var1=$(exit 1) || echo "Trouble with var1"

          # RIGHT
          typeset var1 && var1=$(exit 1) || echo "Trouble with var1"


     To initialize a parameter PARAM to a command output and mark it
     readonly, use typeset -r PARAM or readonly PARAM after the
     parameter assignment statement.

     The flag -n creates a _named reference_ to another parameter.  The
     second parameter need not exist at the time the reference is
     created.  Only the -H, -g, and -r flags may be used in conjunction
     with -n, having their usual meanings.  The -u flag is special and
     may be applied to alter the scope of the reference.  The NAME so
     created may not be an array element nor use a subscript, but the
     VALUE assigned may be any valid parameter name syntax, even a
     subscripted array element (including an associative array element)
     or an array slice, which is evaluated when the named reference is
     expanded.  It is an error for a named reference to refer to itself,
     even indirectly through a chain of references.  When -u is applied
     to a named reference, the parameter identified by VALUE is always
     found in the calling function scope rather than the current local
     scope.  In this case, if there is no such parameter in the calling
     scope, assignments to the named reference may fail, setting $? to
     1.  See *note Parameter Expansion:: and *note Named References::
     for details of the behavior of named references.

     Local function scoping rules for 'typeset' do apply with '-n', so a
     declaration within a function persists only until the end of the
     function unless '-g -n' is specified, and any local parameter (of
     any type) with the same NAME supplants a named reference from a
     surrounding scope.

     A scalar parameter, including an existing named reference, may be
     converted to a new named reference by 'typeset -n NAME', so the
     '-p' option must be included to display the value of a specific
     named reference NAME.

     If no attribute flags are given, and either no NAME arguments are
     present or the flag +m is used, then each parameter name printed is
     preceded by a list of the attributes of that parameter (array,
     association, exported, float, integer, readonly, or undefined for
     autoloaded parameters not yet loaded).  If +m is used with
     attribute flags, and all those flags are introduced with +, the
     matching parameter names are printed but their values are not.

     The following control flags change the behavior of typeset:

     +
          If '+' appears by itself in a separate word as the last
          option, then the names of all parameters (functions with -f)
          are printed, but the values (function bodies) are not.  If
          NAME arguments appear, both those names and their values are
          printed in the form of assignments.  It is an error for any
          other options to follow '+', but the effect of '+' is as if
          all attribute flags which precede it were given with a '+'
          prefix.  For example, 'typeset -U +' is equivalent to 'typeset
          +U' and displays the names of all arrays having the uniqueness
          attribute, whereas 'typeset -f -U +' displays the names of all
          autoloadable functions.  If + is the only option, then type
          information (array, readonly, etc.)  is also printed for each
          parameter, in the same manner as 'typeset +m "*"'.

     -g
          The -g (global) means that any resulting parameter will not be
          restricted to local scope.  Note that this does not
          necessarily mean that the parameter will be global, as the
          flag will apply to any existing parameter (even if unset) from
          an enclosing function.  This flag does not affect the
          parameter after creation, hence it has no effect when listing
          existing parameters, nor does the flag +g have any effect
          except in combination with -m (see below).

     -m
          If the -m flag is given the NAME arguments are taken as
          patterns (use quoting to prevent these from being interpreted
          as file patterns).  With no attribute flags, all parameters
          (or functions with the -f flag) with matching names are
          printed (the shell option TYPESET_SILENT is not used in this
          case).

          If the +g flag is combined with -m, a new local parameter is
          created for every matching parameter that is not already
          local.  Otherwise -m applies all other flags or assignments to
          the existing parameters, except that the -n option cannot
          create named references in this way.

          Except when assignments are made with NAME=VALUE, using +m
          forces the matching parameters and their attributes to be
          printed, even inside a function.  Note that -m is ignored if
          no patterns are given, so 'typeset -m' displays attributes but
          'typeset -a +m' does not.  Ordinary scalar string parameters
          have no attributes, so for those +m prints only the names.

     -p [ N ]
          If the -p option is given, parameters and values are printed
          in the form of a typeset command with an assignment,
          regardless of other flags and options.  Note that the -H flag
          on parameters is respected; no value will be shown for these
          parameters.

          -p may be followed by an optional integer argument.  Currently
          only the value 1 is supported.  In this case arrays and
          associative arrays are printed with newlines between indented
          elements for readability.

          The names and values of readonly special parameters (most of
          the parameters marked '<S>' in *note Parameters Set by the
          Shell::, except those documented as settable) are not printed
          with '-p' because to execute those typeset commands would
          cause errors.  However, these parameters are printed when they
          have been made local to the scope where 'typeset -p' is run.

     -T [ SCALAR[=VALUE] ARRAY[=(VALUE ...)] [ SEP ] ]
          This flag has a different meaning when used with -f; see
          below.  Otherwise the -T option requires zero, two, or three
          arguments to be present.  With no arguments, the list of
          parameters created in this fashion is shown.  With two or
          three arguments, the first two are the name of a scalar and of
          an array parameter (in that order) that will be tied together
          in the manner of $PATH and $path.  The optional third argument
          is a single-character separator which will be used to join the
          elements of the array to form the scalar; if absent, a colon
          is used, as with $PATH.  Only the first character of the
          separator is significant; any remaining characters are
          ignored.  Multibyte characters are not yet supported.

          Only one of the scalar and array parameters may be assigned an
          initial value (the restrictions on assignment forms described
          above also apply).

          Both the scalar and the array may be manipulated as normal.
          If one is unset, the other will automatically be unset too.
          There is no way of untying the variables without unsetting
          them, nor of converting the type of one of them with another
          typeset command; +T does not work, assigning an array to
          SCALAR is an error, and assigning a scalar to ARRAY sets it to
          be a single-element array.

          Note that both 'typeset -xT ...' and 'export -T ...' work, but
          only the scalar will be marked for export.  Setting the value
          using the scalar version causes a split on all separators
          (which cannot be quoted).  It is possible to apply -T to two
          previously tied variables but with a different separator
          character, in which case the variables remain joined as before
          but the separator is changed.

          When an existing scalar is tied to a new array, the value of
          the scalar is preserved but no attribute other than export
          will be preserved.

     Attribute flags that transform the final value (-L, -R, -Z, -l, -u)
     are only applied to the expanded value at the point of a parameter
     expansion expression using '$'.  They are not applied when a
     parameter is retrieved internally by the shell for any purpose.

     The following attribute flags may be specified:

     -A
          The names refer to associative array parameters; see *note
          Array Parameters::.

     -L [ N ]
          Left justify and remove leading blanks from the value when the
          parameter is expanded.  If N is nonzero, it defines the width
          of the field.  If N is zero, the width is determined by the
          width of the value of the first assignment.  In the case of
          numeric parameters, the length of the complete value assigned
          to the parameter is used to determine the width, not the value
          that would be output.

          The width is the count of characters, which may be multibyte
          characters if the MULTIBYTE option is in effect.  Note that
          the screen width of the character is not taken into account;
          if this is required, use padding with parameter expansion
          flags ${(ml...)...} as described in *note Parameter Expansion
          Flags::.

          When the parameter is expanded, it is filled on the right with
          blanks or truncated if necessary to fit the field.  Note
          truncation can lead to unexpected results with numeric
          parameters.  Leading zeros are removed if the -Z flag is also
          set.

     -R [ N ]
          Similar to -L, except that right justification is used; when
          the parameter is expanded, the field is left filled with
          blanks or truncated from the end.  May not be combined with
          the -Z flag.

     -U
          For arrays (but not for associative arrays), keep only the
          first occurrence of each duplicated value.  This may also be
          set for tied parameters (see -T) or colon-separated special
          parameters like PATH or FIGNORE, etc.  Note the flag takes
          effect on assignment, and the type of the variable being
          assigned to is determinative; for variables with shared values
          it is therefore recommended to set the flag for all
          interfaces, e.g.  'typeset -U PATH path'.

          This flag has a different meaning when used with -f; see
          below.

     -Z [ N ]
          Specially handled if set along with the -L flag.  Otherwise,
          similar to -R, except that leading zeros are used for padding
          instead of blanks if the first non-blank character is a digit.
          Numeric parameters are specially handled: they are always
          eligible for padding with zeroes, and the zeroes are inserted
          at an appropriate place in the output.

     -a
          The names refer to array parameters.  An array parameter may
          be created this way, but it may be assigned to in the typeset
          statement only if the reserved word form of typeset is enabled
          (as it is by default).  When displaying, both normal and
          associative arrays are shown.

     -f
          The names refer to functions rather than parameters.  No
          assignments can be made, and the only other valid flags are
          -t, -T, -k, -u, -U and -z.  The flag -t turns on execution
          tracing for this function; the flag -T does the same, but
          turns off tracing for any named (not anonymous) function
          called from the present one, unless that function also has the
          -t or -T flag.  The -u and -U flags cause the function to be
          marked for autoloading; -U also causes alias expansion to be
          suppressed when the function is loaded.  See the description
          of the 'autoload' builtin for details.

          Note that the builtin functions provides the same basic
          capabilities as typeset -f but gives access to a few extra
          options; autoload gives further additional options for the
          case typeset -fu and typeset -fU.

     -h
          Hide: only useful for special parameters (those marked '<S>'
          in the table in *note Parameters Set by the Shell::), and for
          local parameters with the same name as a special parameter,
          though harmless for others.  A special parameter with this
          attribute will not retain its special effect when made local.
          Thus after 'typeset -h PATH', a function containing 'typeset
          PATH' will create an ordinary local parameter without the
          usual behaviour of PATH.  Alternatively, the local parameter
          may itself be given this attribute; hence inside a function
          'typeset -h PATH' creates an ordinary local parameter and the
          special PATH parameter is not altered in any way.  It is also
          possible to create a local parameter using 'typeset +h
          SPECIAL', where the local copy of SPECIAL will retain its
          special properties regardless of having the -h attribute.
          Global special parameters loaded from shell modules (for
          example, those in zsh/mapfile and zsh/parameter) are
          automatically given the -h attribute to avoid name clashes.

     -H
          Hide value: specifies that typeset will not display the value
          of the parameter when listing parameters; the display for such
          parameters is always as if the '+' flag were given, but use of
          the parameter is in other respects normal.  This effect does
          not apply when the parameter is specified by name or by
          pattern with the -m option.  This is on by default for the
          parameters in the zsh/parameter and zsh/mapfile modules.
          Note, however, that unlike the -h flag this is also useful for
          non-special parameters.

     -i [ N ]
          Use an internal integer representation.  If N is nonzero it
          defines the output arithmetic base, otherwise it is determined
          by the first assignment.  Bases from 2 to 36 inclusive are
          allowed.

     -E [ N ]
          Use an internal double-precision floating point
          representation.  On output the variable will be converted to
          scientific notation.  If N is nonzero it defines the number of
          significant figures to display; the default is ten.

     -F [ N ]
          Use an internal double-precision floating point
          representation.  On output the variable will be converted to
          fixed-point decimal notation.  If N is nonzero it defines the
          number of digits to display after the decimal point; the
          default is ten.

     -l
          Convert the result to lower case whenever the parameter is
          expanded.  The value is _not_ converted when assigned.

     -r
          The given NAMEs are marked readonly.  Note that if NAME is a
          special parameter, the readonly attribute can be turned on,
          but cannot then be turned off.

          If the POSIX_BUILTINS option is set, the readonly attribute is
          more restrictive: unset variables can be marked readonly and
          cannot then be set; furthermore, the readonly attribute cannot
          be removed from any variable.

          It is still possible to change other attributes of the
          variable though, some of which like -U or -Z would affect the
          value.  More generally, the readonly attribute should not be
          relied on as a security mechanism.

          Note that in zsh (like in pdksh but unlike most other shells)
          it is still possible to create a local variable of the same
          name as this is considered a different variable (though this
          variable, too, can be marked readonly).  Special variables
          that have been made readonly retain their value and readonly
          attribute when made local.

     -t
          Tags the named parameters.  Tags only exist to flag the
          parameter for the user's own purposes -- the list of tagged
          parameters can be queried using 'typeset -t'.  Tags have no
          other use.  Note that the -t flag has a different meaning when
          used with -f; see above.

     -u
          Convert the result to upper case whenever the parameter is
          expanded.  The value is _not_ converted when assigned.  This
          flag has different meanings when used with -f or -n; see
          above.

     -x
          Mark for automatic export to the environment of subsequently
          executed commands.  If the option GLOBAL_EXPORT is set, this
          implies the option -g, unless +g is also explicitly given; in
          other words the parameter is not made local to the enclosing
          function.  This is for compatibility with previous versions of
          zsh.

ulimit [ -HSa ] [ { -bcdfiklmnpqrsTtvwx | -N RESOURCE } [ LIMIT ] ... ]
     Set or display resource limits of the shell and the processes
     started by the shell.  The value of LIMIT can be a number in the
     unit specified below or one of the values 'unlimited', which
     removes the limit on the resource, or 'hard', which uses the
     current value of the hard limit on the resource.

     By default, only soft limits are manipulated.  If the -H flag is
     given use hard limits instead of soft limits.  If the -S flag is
     given together with the -H flag set both hard and soft limits.

     If no options are used, the file size limit (-f) is assumed.

     If LIMIT is omitted the current value of the specified resources
     are printed.  When more than one resource value is printed, the
     limit name and unit is printed before each value.

     When looping over multiple resources, the shell will abort
     immediately if it detects a badly formed argument.  However, if it
     fails to set a limit for some other reason it will continue trying
     to set the remaining limits.

     Not all the following resources are supported on all systems.
     Running ulimit -a will show which are supported.

     -a
          List all of the current resource limits.
     -b
          Socket buffer size in bytes (N.B. not kilobytes)
     -c
          512-byte blocks on the size of core dumps.
     -d
          Kilobytes on the size of the data segment.
     -e
          Maximum nice value.
     -f
          512-byte blocks on the size of files written.
     -i
          The number of pending signals.
     -k
          The number of kqueues allocated.
     -l
          Kilobytes on the size of locked-in memory.
     -m
          Kilobytes on the size of physical memory.
     -n
          Open file descriptors.
     -o
          Maximum number of POSIX thread library objects.
     -p
          The number of pseudo-terminals.
     -q
          Bytes in POSIX message queues.
     -r
          Maximum real time priority.  On some systems where this is not
          available, such as NetBSD, this has the same effect as -T for
          compatibility with sh.
     -s
          Kilobytes on the size of the stack.
     -T
          The number of simultaneous threads available to the user.
     -t
          CPU seconds to be used.
     -u
          The number of processes available to the user.
     -v
          Kilobytes on the size of virtual memory.  On some systems this
          refers to the limit called 'address space'.
     -w
          Kilobytes on the size of swapped out memory.
     -x
          The number of locks on files.
     -y
          Maximum size of buffers for pipes/fifos.

     A resource may also be specified by integer in the form '-N
     RESOURCE', where RESOURCE corresponds to the integer defined for
     the resource by the operating system.  This may be used to set the
     limits for resources known to the shell which do not correspond to
     option letters.  Such limits will be shown by number in the output
     of 'ulimit -a'.

     The number may alternatively be out of the range of limits compiled
     into the shell.  The shell will try to read or write the limit
     anyway, and will report an error if this fails.

umask [ -S ] [ MASK ]
     The umask is set to MASK.  MASK can be either an octal number or a
     symbolic value as described in the chmod(1) man page.  If MASK is
     omitted, the current value is printed.  The -S option causes the
     mask to be printed as a symbolic value.  Otherwise, the mask is
     printed as an octal number.  Note that in the symbolic form the
     permissions you specify are those which are to be allowed (not
     denied) to the users specified.

unalias [ -ams ] NAME ...
     Removes aliases.  This command works the same as unhash -a, except
     that the -a option removes all regular or global aliases, or with
     -s all suffix aliases: in this case no NAME arguments may appear.
     The options -m (remove by pattern) and -s without -a (remove listed
     suffix aliases) behave as for unhash -a.  Note that the meaning of
     -a is different between unalias and unhash.

unfunction
     Same as unhash -f.

unhash [ -adfms ] NAME ...
     Remove the element named NAME from an internal hash table.  The
     default is remove elements from the command hash table.  The -a
     option causes unhash to remove regular or global aliases; note when
     removing a global aliases that the argument must be quoted to
     prevent it from being expanded before being passed to the command.
     The -s option causes unhash to remove suffix aliases.  The -f
     option causes unhash to remove shell functions.  The -d options
     causes unhash to remove named directories.  If the -m flag is given
     the arguments are taken as patterns (should be quoted) and all
     elements of the corresponding hash table with matching names will
     be removed.

unlimit [ -hs ] RESOURCE ...
     The resource limit for each RESOURCE is set to the hard limit.  If
     the -h flag is given and the shell has appropriate privileges, the
     hard resource limit for each RESOURCE is removed.  The resources of
     the shell process are only changed if the -s flag is given.

     The unlimit command is not made available by default when the shell
     starts in a mode emulating another shell.  It can be made available
     with the command 'zmodload -F zsh/rlimits b:unlimit'.

unset [ -fmv ] [ -n ] NAME ...
     Each named parameter is unset.  Local parameters remain local even
     if unset; they appear unset within scope, but the previous value
     will still reappear when the scope ends.

     Individual elements of associative array parameters may be unset by
     using subscript syntax on NAME, which should be quoted (or the
     entire command prefixed with noglob) to protect the subscript from
     filename generation.

     If the -m flag is specified the arguments are taken as patterns
     (should be quoted) and all parameters with matching names are
     unset.  Note that this cannot be used when unsetting associative
     array elements, as the subscript will be treated as part of the
     pattern.

     The -v flag specifies that NAME refers to parameters.  This is the
     default behaviour.  If the -n option is supplied, and NAME is a a
     named reference, NAME will be unset rather than the variable it
     references.

     unset -f is equivalent to unfunction.  The -n option has no effect
     with -f.

unsetopt [ {+|-}OPTIONS | {+|-}o OPTION_NAME ] [ NAME ... ]
     Unset the options for the shell.  All options specified either with
     flags or by name are unset.  If no arguments are supplied, the
     names of all options currently unset are printed.  If the -m flag
     is given the arguments are taken as patterns (which should be
     quoted to preserve them from being interpreted as glob patterns),
     and all options with names matching these patterns are unset.

vared
     See *note Zle Builtins::.

wait [ JOB ... ]
     Wait for the specified jobs or processes.  If JOB is not given then
     all currently active child processes are waited for.  Each JOB can
     be either a job specification or the process ID of a job in the job
     table.  The exit status from this command is that of the job waited
     for.  If JOB represents an unknown job or process ID, a warning is
     printed (unless the POSIX_BUILTINS option is set) and the exit
     status is 127.

     It is possible to wait for recent processes (specified by process
     ID, not by job) that were running in the background even if the
     process has exited.  Typically the process ID will be recorded by
     capturing the value of the variable $! immediately after the
     process has been started.  There is a limit on the number of
     process IDs remembered by the shell; this is given by the value of
     the system configuration parameter CHILD_MAX.  When this limit is
     reached, older process IDs are discarded, least recently started
     processes first.

     Note there is no protection against the process ID wrapping, i.e.
     if the wait is not executed soon enough there is a chance the
     process waited for is the wrong one.  A conflict implies both
     process IDs have been generated by the shell, as other processes
     are not recorded, and that the user is potentially interested in
     both, so this problem is intrinsic to process IDs.

whence [ -vcwfpamsS ] [ -x NUM ] NAME ...
     For each NAME, indicate how it would be interpreted if used as a
     command name.

     If NAME is not an alias, built-in command, external command, shell
     function, hashed command, or a reserved word, the exit status shall
     be non-zero, and -- if -v, -c, or -w was passed -- a message will
     be written to standard output.  (This is different from other
     shells that write that message to standard error.)

     whence is most useful when NAME is only the last path component of
     a command, i.e.  does not include a '/'; in particular, pattern
     matching only succeeds if just the non-directory component of the
     command is passed.

     -v
          Produce a more verbose report.

     -c
          Print the results in a ‘csh’-like format.  This takes
          precedence over -v.

     -w
          For each NAME, print 'NAME: WORD' where WORD is one of alias,
          builtin, command, function, hashed, reserved or none,
          according as NAME corresponds to an alias, a built-in command,
          an external command, a shell function, a command defined with
          the hash builtin, a reserved word, or is not recognised.  This
          takes precedence over -v and -c.

     -f
          Causes the contents of a shell function to be displayed, which
          would otherwise not happen unless the -c flag were used.

     -p
          Do a path search for NAME even if it is an alias, reserved
          word, shell function or builtin.

     -a
          Do a search for all occurrences of NAME throughout the command
          path.  Normally only the first occurrence is printed.  When
          combined with -m, only names appearing in the command hash
          table are searched, but all occurrences of those names are
          printed.

     -m
          The arguments are taken as patterns (pattern characters should
          be quoted), and the information is displayed for each entry in
          the command hash table matching one of these patterns.  The
          hash table is first refilled, in case of changes to PATH.

     -s
          If a pathname contains symlinks, print the symlink-free
          pathname as well.

     -S
          As -s, but if the pathname had to be resolved by following
          multiple symlinks, the intermediate steps are printed, too.
          The symlink resolved at each step might be anywhere in the
          path.

     -x NUM
          Expand tabs when outputting shell functions using the -c
          option.  This has the same effect as the -x option to the
          functions builtin.

where [ -wpmsS ] [ -x NUM ] NAME ...
     Equivalent to whence -ca.

which [ -wpamsS ] [ -x NUM ] NAME ...
     Equivalent to whence -c.

zcompile [ -U ] [ -z | -k ] [ -R | -M ] FILE [ NAME ... ]
zcompile -ca [ -m ] [ -R | -M ] FILE [ NAME ... ]
zcompile -t FILE [ NAME ... ]
     This builtin command can be used to compile functions or scripts,
     storing the compiled form in a file, and to examine files
     containing the compiled form.  This allows faster autoloading of
     functions and sourcing of scripts by avoiding parsing of the text
     when the files are read.

     The first form (without the -c, -a or -t options) creates a
     compiled file.  If only the FILE argument is given, the output file
     has the name 'FILE.zwc' and will be placed in the same directory as
     the FILE.  The shell will load the compiled file instead of the
     normal function file when the function is autoloaded; see *note
     Autoloading Functions:: for a description of how autoloaded
     functions are searched.  The extension .zwc stands for 'zsh word
     code'.

     If there is at least one NAME argument, all the named files are
     compiled into the output FILE given as the first argument.  If FILE
     does not end in .zwc, this extension is automatically appended.
     Files containing multiple compiled functions are called 'digest'
     files, and are intended to be used as elements of the FPATH/fpath
     special array.

     The second form, with the -c or -a options, writes the compiled
     definitions for all the named functions into FILE.  For -c, the
     names must be functions currently defined in the shell, not those
     marked for autoloading.  Undefined functions that are marked for
     autoloading may be written by using the -a option, in which case
     the fpath is searched and the contents of the definition files for
     those functions, if found, are compiled into FILE.  If both -c and
     -a are given, names of both defined functions and functions marked
     for autoloading may be given.  In either case, the functions in
     files written with the -c or -a option will be autoloaded as if the
     KSH_AUTOLOAD option were unset.

     The reason for handling loaded and not-yet-loaded functions with
     different options is that some definition files for autoloading
     define multiple functions, including the function with the same
     name as the file, and, at the end, call that function.  In such
     cases the output of 'zcompile -c' does not include the additional
     functions defined in the file, and any other initialization code in
     the file is lost.  Using 'zcompile -a' captures all this extra
     information.

     If the -m option is combined with -c or -a, the NAMEs are used as
     patterns and all functions whose names match one of these patterns
     will be written.  If no NAME is given, the definitions of all
     functions currently defined or marked as autoloaded will be
     written.

     Note the second form cannot be used for compiling functions that
     include redirections as part of the definition rather than within
     the body of the function; for example

          fn1() { { ... } >~/logfile }

     can be compiled but

          fn1() { ... } >~/logfile

     cannot.  It is possible to use the first form of zcompile to
     compile autoloadable functions that include the full function
     definition instead of just the body of the function.

     The third form, with the -t option, examines an existing compiled
     file.  Without further arguments, the names of the original files
     compiled into it are listed.  The first line of output shows the
     version of the shell which compiled the file and how the file will
     be used (i.e.  by reading it directly or by mapping it into
     memory).  With arguments, nothing is output and the return status
     is set to zero if definitions for _all_ NAMEs were found in the
     compiled file, and non-zero if the definition for at least one NAME
     was not found.

     Other options:

     -U
          Aliases are not expanded when compiling the NAMEd files.

     -R
          When the compiled file is read, its contents are copied into
          the shell's memory, rather than memory-mapped (see -M).  This
          happens automatically on systems that do not support memory
          mapping.

          When compiling scripts instead of autoloadable functions, it
          is often desirable to use this option; otherwise the whole
          file, including the code to define functions which have
          already been defined, will remain mapped, consequently wasting
          memory.

     -M
          The compiled file is mapped into the shell's memory when read.
          This is done in such a way that multiple instances of the
          shell running on the same host will share this mapped file.
          If neither -R nor -M is given, the zcompile builtin decides
          what to do based on the size of the compiled file.

     -k
     -z
          These options are used when the compiled file contains
          functions which are to be autoloaded.  If -z is given, the
          function will be autoloaded as if the KSH_AUTOLOAD option is
          _not_ set, even if it is set at the time the compiled file is
          read, while if the -k is given, the function will be loaded as
          if KSH_AUTOLOAD _is_ set.  These options also take precedence
          over any -k or -z options specified to the autoload builtin.
          If neither of these options is given, the function will be
          loaded as determined by the setting of the KSH_AUTOLOAD option
          at the time the compiled file is read.

          These options may also appear as many times as necessary
          between the listed NAMEs to specify the loading style of all
          following functions, up to the next -k or -z.

     The created file always contains two versions of the compiled
     format, one for big-endian machines and one for small-endian
     machines.  The upshot of this is that the compiled file is machine
     independent and if it is read or mapped, only one half of the file
     is actually used (and mapped).

zformat
     See *note The zsh/zutil Module::.

zftp
     See *note The zsh/zftp Module::.

zle
     See *note Zle Builtins::.

zmodload [ -dL ] [ -s ] [ ... ]
zmodload -F [ -alLme -P PARAM ] MODULE [ [+-]FEATURE ... ]
zmodload -e [ -A ] [ ... ]
zmodload [ -a [ -bcpf [ -I ] ] ] [ -iL ] ...
zmodload -u [ -abcdpf [ -I ] ] [ -iL ] ...
zmodload -A [ -L ] [ MODALIAS[=MODULE] ... ]
zmodload -R MODALIAS ...
     Performs operations relating to zsh's loadable modules.  Loading of
     modules while the shell is running ('dynamical loading') is not
     available on all operating systems, or on all installations on a
     particular operating system, although the zmodload command itself
     is always available and can be used to manipulate modules built
     into versions of the shell executable without dynamical loading.

     Without arguments the names of all currently loaded binary modules
     are printed.  The -L option causes this list to be in the form of a
     series of zmodload commands.  Forms with arguments are:

     zmodload [ -is ] NAME ...
     zmodload -u [ -i ] NAME ...
          In the simplest case, zmodload loads a binary module.  The
          module must be in a file with a name consisting of the
          specified NAME followed by a standard suffix, usually '.so'
          ('.sl' on HPUX). If the module to be loaded is already loaded
          the duplicate module is ignored.  If zmodload detects an
          inconsistency, such as an invalid module name or circular
          dependency list, the current code block is aborted.  If it is
          available, the module is loaded if necessary, while if it is
          not available, non-zero status is silently returned.  The
          option -i is accepted for compatibility but has no effect.

          The NAMEd module is searched for in the same way a command is,
          using $module_path instead of $path.  However, the path search
          is performed even when the module name contains a '/', which
          it usually does.  There is no way to prevent the path search.

          If the module supports features (see below), zmodload tries to
          enable all features when loading a module.  If the module was
          successfully loaded but not all features could be enabled,
          zmodload returns status 2.

          If the option -s is given, no error is printed if the module
          was not available (though other errors indicating a problem
          with the module are printed).  The return status indicates if
          the module was loaded.  This is appropriate if the caller
          considers the module optional.

          With -u, zmodload unloads modules.  The same NAME must be
          given that was given when the module was loaded, but it is not
          necessary for the module to exist in the file system.  The -i
          option suppresses the error if the module is already unloaded
          (or was never loaded).

          Each module has a boot and a cleanup function.  The module
          will not be loaded if its boot function fails.  Similarly a
          module can only be unloaded if its cleanup function runs
          successfully.

     zmodload -F [ -almLe -P PARAM ] MODULE [ [+-]FEATURE ... ]
          zmodload -F allows more selective control over the features
          provided by modules.  With no options apart from -F, the
          module named MODULE is loaded, if it was not already loaded,
          and the list of FEATUREs is set to the required state.  If no
          FEATUREs are specified, the module is loaded, if it was not
          already loaded, but the state of features is unchanged.  Each
          feature may be preceded by a + to turn the feature on, or - to
          turn it off; the + is assumed if neither character is present.
          Any feature not explicitly mentioned is left in its current
          state; if the module was not previously loaded this means any
          such features will remain disabled.  The return status is zero
          if all features were set, 1 if the module failed to load, and
          2 if some features could not be set (for example, a parameter
          couldn't be added because there was a different parameter of
          the same name) but the module was loaded.

          The standard features are builtins, conditions, parameters and
          math functions; these are indicated by the prefix 'b:', 'c:'
          ('C:' for an infix condition), 'p:' and 'f:', respectively,
          followed by the name that the corresponding feature would have
          in the shell.  For example, 'b:strftime' indicates a builtin
          named strftime and p:EPOCHSECONDS indicates a parameter named
          EPOCHSECONDS.  The module may provide other ('abstract')
          features of its own as indicated by its documentation; these
          have no prefix.

          With -l or -L, features provided by the module are listed.
          With -l alone, a list of features together with their states
          is shown, one feature per line.  With -L alone, a zmodload -F
          command that would cause enabled features of the module to be
          turned on is shown.  With -lL, a zmodload -F command that
          would cause all the features to be set to their current state
          is shown.  If one of these combinations is given with the
          option -P PARAM then the parameter PARAM is set to an array of
          features, either features together with their state or (if -L
          alone is given) enabled features.

          With the option -L the module name may be omitted; then a list
          of all enabled features for all modules providing features is
          printed in the form of zmodload -F commands.  If -l is also
          given, the state of both enabled and disabled features is
          output in that form.

          A set of features may be provided together with -l or -L and a
          module name; in that case only the state of those features is
          considered.  Each feature may be preceded by + or - but the
          character has no effect.  If no set of features is provided,
          all features are considered.

          With -e, the command first tests that the module is loaded; if
          it is not, status 1 is returned.  If the module is loaded, the
          list of features given as an argument is examined.  Any
          feature given with no prefix is simply tested to see if the
          module provides it; any feature given with a prefix + or - is
          tested to see if is provided and in the given state.  If the
          tests on all features in the list succeed, status 0 is
          returned, else status 1.

          With -m, each entry in the given list of features is taken as
          a pattern to be matched against the list of features provided
          by the module.  An initial + or - must be given explicitly.
          This may not be combined with the -a option as autoloads must
          be specified explicitly.

          With -a, the given list of features is marked for autoload
          from the specified module, which may not yet be loaded.  An
          optional + may appear before the feature name.  If the feature
          is prefixed with -, any existing autoload is removed.  The
          options -l and -L may be used to list autoloads.  Autoloading
          is specific to individual features; when the module is loaded
          only the requested feature is enabled.  Autoload requests are
          preserved if the module is subsequently unloaded until an
          explicit 'zmodload -Fa MODULE -FEATURE' is issued.  It is not
          an error to request an autoload for a feature of a module that
          is already loaded.

          When the module is loaded each autoload is checked against the
          features actually provided by the module; if the feature is
          not provided the autoload request is deleted.  A warning
          message is output; if the module is being loaded to provide a
          different feature, and that autoload is successful, there is
          no effect on the status of the current command.  If the module
          is already loaded at the time when zmodload -Fa is run, an
          error message is printed and status 1 returned.

          zmodload -Fa can be used with the -l, -L, -e and -P options
          for listing and testing the existence of autoloadable
          features.  In this case -l is ignored if -L is specified.
          zmodload -FaL with no module name lists autoloads for all
          modules.

          Note that only standard features as described above can be
          autoloaded; other features require the module to be loaded
          before enabling.

     zmodload -d [ -L ] [ NAME ]
     zmodload -d NAME DEP ...
     zmodload -ud NAME [ DEP ... ]
          The -d option can be used to specify module dependencies.  The
          modules named in the second and subsequent arguments will be
          loaded before the module named in the first argument.

          With -d and one argument, all dependencies for that module are
          listed.  With -d and no arguments, all module dependencies are
          listed.  This listing is by default in a Makefile-like format.
          The -L option changes this format to a list of zmodload -d
          commands.

          If -d and -u are both used, dependencies are removed.  If only
          one argument is given, all dependencies for that module are
          removed.

     zmodload -ab [ -L ]
     zmodload -ab [ -i ] NAME [ BUILTIN ... ]
     zmodload -ub [ -i ] BUILTIN ...
          The -ab option defines autoloaded builtins.  It defines the
          specified BUILTINs.  When any of those builtins is called, the
          module specified in the first argument is loaded and all its
          features are enabled (for selective control of features use
          'zmodload -F -a' as described above).  If only the NAME is
          given, one builtin is defined, with the same name as the
          module.  -i suppresses the error if the builtin is already
          defined or autoloaded, but not if another builtin of the same
          name is already defined.

          With -ab and no arguments, all autoloaded builtins are listed,
          with the module name (if different) shown in parentheses after
          the builtin name.  The -L option changes this format to a list
          of zmodload -a commands.

          If -b is used together with the -u option, it removes builtins
          previously defined with -ab.  This is only possible if the
          builtin is not yet loaded.  -i suppresses the error if the
          builtin is already removed (or never existed).

          Autoload requests are retained if the module is subsequently
          unloaded until an explicit 'zmodload -ub BUILTIN' is issued.

     zmodload -ac [ -IL ]
     zmodload -ac [ -iI ] NAME [ COND ... ]
     zmodload -uc [ -iI ] COND ...
          The -ac option is used to define autoloaded condition codes.
          The COND strings give the names of the conditions defined by
          the module.  The optional -I option is used to define infix
          condition names.  Without this option prefix condition names
          are defined.

          If given no condition names, all defined names are listed (as
          a series of zmodload commands if the -L option is given).

          The -uc option removes definitions for autoloaded conditions.

     zmodload -ap [ -L ]
     zmodload -ap [ -i ] NAME [ PARAMETER ... ]
     zmodload -up [ -i ] PARAMETER ...
          The -p option is like the -b and -c options, but makes
          zmodload work on autoloaded parameters instead.

     zmodload -af [ -L ]
     zmodload -af [ -i ] NAME [ FUNCTION ... ]
     zmodload -uf [ -i ] FUNCTION ...
          The -f option is like the -b, -p, and -c options, but makes
          zmodload work on autoloaded math functions instead.

     zmodload -a [ -L ]
     zmodload -a [ -i ] NAME [ BUILTIN ... ]
     zmodload -ua [ -i ] BUILTIN ...
          Equivalent to -ab and -ub.

     zmodload -e [ -A ] [ STRING ... ]
          The -e option without arguments lists all loaded modules; if
          the -A option is also given, module aliases corresponding to
          loaded modules are also shown.  If arguments are provided,
          nothing is printed; the return status is set to zero if all
          STRINGs given as arguments are names of loaded modules and to
          one if at least on STRING is not the name of a loaded module.
          This can be used to test for the availability of things
          implemented by modules.  In this case, any aliases are
          automatically resolved and the -A flag is not used.

     zmodload -A [ -L ] [ MODALIAS[=MODULE] ... ]
          For each argument, if both MODALIAS and MODULE are given,
          define MODALIAS to be an alias for the module MODULE.  If the
          module MODALIAS is ever subsequently requested, either via a
          call to zmodload or implicitly, the shell will attempt to load
          MODULE instead.  If MODULE is not given, show the definition
          of MODALIAS.  If no arguments are given, list all defined
          module aliases.  When listing, if the -L flag was also given,
          list the definition as a zmodload command to recreate the
          alias.

          The existence of aliases for modules is completely independent
          of whether the name resolved is actually loaded as a module:
          while the alias exists, loading and unloading the module under
          any alias has exactly the same effect as using the resolved
          name, and does not affect the connection between the alias and
          the resolved name which can be removed either by zmodload -R
          or by redefining the alias.  Chains of aliases (i.e.  where
          the first resolved name is itself an alias) are valid so long
          as these are not circular.  As the aliases take the same
          format as module names, they may include path separators: in
          this case, there is no requirement for any part of the path
          named to exist as the alias will be resolved first.  For
          example, 'any/old/alias' is always a valid alias.

          Dependencies added to aliased modules are actually added to
          the resolved module; these remain if the alias is removed.  It
          is valid to create an alias whose name is one of the standard
          shell modules and which resolves to a different module.
          However, if a module has dependencies, it will not be possible
          to use the module name as an alias as the module will already
          be marked as a loadable module in its own right.

          Apart from the above, aliases can be used in the zmodload
          command anywhere module names are required.  However, aliases
          will not be shown in lists of loaded modules with a bare
          'zmodload'.

     zmodload -R MODALIAS ...
          For each MODALIAS argument that was previously defined as a
          module alias via zmodload -A, delete the alias.  If any was
          not defined, an error is caused and the remainder of the line
          is ignored.

     Note that zsh makes no distinction between modules that were linked
     into the shell and modules that are loaded dynamically.  In both
     cases this builtin command has to be used to make available the
     builtins and other things defined by modules (unless the module is
     autoloaded on these definitions).  This is true even for systems
     that don't support dynamic loading of modules.

zparseopts
     See *note The zsh/zutil Module::.

zprof
     See *note The zsh/zprof Module::.

zpty
     See *note The zsh/zpty Module::.

zregexparse
     See *note The zsh/zutil Module::.

zsocket
     See *note The zsh/net/socket Module::.

zstyle
     See *note The zsh/zutil Module::.

ztcp
     See *note The zsh/net/tcp Module::.


File: zsh.info,  Node: Zsh Line Editor,  Next: Completion Widgets,  Prev: Shell Builtin Commands,  Up: Top

18 Zsh Line Editor
******************

18.1 Description
================

If the ZLE option is set (which it is by default in interactive shells)
and the shell input is attached to the terminal, the user is able to
edit command lines.

There are two display modes.  The first, multiline mode, is the default.
It only works if the TERM parameter is set to a valid terminal type that
can move the cursor up.  The second, single line mode, is used if TERM
is invalid or incapable of moving the cursor up, or if the
SINGLE_LINE_ZLE option is set.  This mode is similar to ‘ksh’, and uses
no termcap sequences.  If TERM is "emacs", the ZLE option will be unset
by default.

The parameters BAUD, COLUMNS, and LINES are also used by the line
editor.  See *note Parameters Used by the Shell::.

The parameter zle_highlight is also used by the line editor; see *note
Character Highlighting::.  Highlighting of special characters and the
region between the cursor and the mark (as set with set-mark-command in
Emacs mode, or by visual-mode in Vi mode) is enabled by default; consult
this reference for more information.  Irascible conservatives will wish
to know that all highlighting may be disabled by the following setting:

     zle_highlight=(none)

In many places, references are made to the numeric argument.  This can
by default be entered in emacs mode by holding the alt key and typing a
number, or pressing escape before each digit, and in vi command mode by
typing the number before entering a command.  Generally the numeric
argument causes the next command entered to be repeated the specified
number of times, unless otherwise noted below; this is implemented by
the digit-argument widget.  See also *note Arguments:: for some other
ways the numeric argument can be modified.

* Menu:

* Keymaps::
* Zle Builtins::
* Zle Widgets::
* User-Defined Widgets::
* Standard Widgets::
* Character Highlighting::


File: zsh.info,  Node: Keymaps,  Next: Zle Builtins,  Up: Zsh Line Editor

18.2 Keymaps
============

A keymap in ZLE contains a set of bindings between key sequences and ZLE
commands.  The empty key sequence cannot be bound.

There can be any number of keymaps at any time, and each keymap has one
or more names.  If all of a keymap's names are deleted, it disappears.
bindkey can be used to manipulate keymap names.

Initially, there are eight keymaps:

emacs
     EMACS emulation
viins
     vi emulation - insert mode
vicmd
     vi emulation - command mode
viopp
     vi emulation - operator pending
visual
     vi emulation - selection active
isearch
     incremental search mode
command
     read a command name
.safe
     fallback keymap

The '.safe' keymap is special.  It can never be altered, and the name
can never be removed.  However, it can be linked to other names, which
can be removed.  In the future other special keymaps may be added; users
should avoid using names beginning with '.' for their own keymaps.

In addition to these names, either 'emacs' or 'viins' is also linked to
the name 'main'.  If one of the VISUAL or EDITOR environment variables
contain the string 'vi' when the shell starts up then it will be
'viins', otherwise it will be 'emacs'.  bindkey's -e and -v options
provide a convenient way to override this default choice.

When the editor starts up, it will select the 'main' keymap.  If that
keymap doesn't exist, it will use '.safe' instead.

In the '.safe' keymap, each single key is bound to self-insert, except
for ^J (line feed) and ^M (return) which are bound to accept-line.  This
is deliberately not pleasant to use; if you are using it, it means you
deleted the main keymap, and you should put it back.

18.2.1 Reading Commands
-----------------------

When ZLE is reading a command from the terminal, it may read a sequence
that is bound to some command and is also a prefix of a longer bound
string.  In this case ZLE will wait a certain time to see if more
characters are typed, and if not (or they don't match any longer string)
it will execute the binding.  This timeout is defined by the KEYTIMEOUT
parameter; its default is 0.4 sec.  There is no timeout if the prefix
string is not itself bound to a command.

The key timeout is also applied when ZLE is reading the bytes from a
multibyte character string when it is in the appropriate mode.  (This
requires that the shell was compiled with multibyte mode enabled;
typically also the locale has characters with the UTF-8 encoding,
although any multibyte encoding known to the operating system is
supported.)  If the second or a subsequent byte is not read within the
timeout period, the shell acts as if ? were typed and resets the input
state.

As well as ZLE commands, key sequences can be bound to other strings, by
using 'bindkey -s'.  When such a sequence is read, the replacement
string is pushed back as input, and the command reading process starts
again using these fake keystrokes.  This input can itself invoke further
replacement strings, but in order to detect loops the process will be
stopped if there are twenty such replacements without a real command
being read.

A key sequence typed by the user can be turned into a command name for
use in user-defined widgets with the read-command widget, described in
*note Miscellaneous::.

18.2.2 Local Keymaps
--------------------

While for normal editing a single keymap is used exclusively, in many
modes a local keymap allows for some keys to be customised.  For
example, in an incremental search mode, a binding in the isearch keymap
will override a binding in the main keymap but all keys that are not
overridden can still be used.

If a key sequence is defined in a local keymap, it will hide a key
sequence in the global keymap that is a prefix of that sequence.  An
example of this occurs with the binding of iw in viopp as this hides the
binding of i in vicmd.  However, a longer sequence in the global keymap
that shares the same prefix can still apply so for example the binding
of ^Xa in the global keymap will be unaffected by the binding of ^Xb in
the local keymap.


File: zsh.info,  Node: Zle Builtins,  Next: Zle Widgets,  Prev: Keymaps,  Up: Zsh Line Editor

18.3 Zle Builtins
=================

The ZLE module contains three related builtin commands.  The bindkey
command manipulates keymaps and key bindings; the vared command invokes
ZLE on the value of a shell parameter; and the zle command manipulates
editing widgets and allows command line access to ZLE commands from
within shell functions.

bindkey [ OPTIONS ] -l [ -L ] [ KEYMAP ... ]
bindkey [ OPTIONS ] -d
bindkey [ OPTIONS ] -D KEYMAP ...
bindkey [ OPTIONS ] -A OLD-KEYMAP NEW-KEYMAP
bindkey [ OPTIONS ] -N NEW-KEYMAP [ OLD-KEYMAP ]
bindkey [ OPTIONS ] -m
bindkey [ OPTIONS ] -r IN-STRING ...
bindkey [ OPTIONS ] -s IN-STRING OUT-STRING ...
bindkey [ OPTIONS ] IN-STRING COMMAND ...
bindkey [ OPTIONS ] [ IN-STRING ]
     bindkey's options can be divided into three categories: keymap
     selection for the current command, operation selection, and others.
     The keymap selection options are:

     -e
          Selects keymap 'emacs' for any operations by the current
          command, and also links 'emacs' to 'main' so that it is
          selected by default the next time the editor starts.

     -v
          Selects keymap 'viins' for any operations by the current
          command, and also links 'viins' to 'main' so that it is
          selected by default the next time the editor starts.

     -a
          Selects keymap 'vicmd' for any operations by the current
          command.

     -M KEYMAP
          The KEYMAP specifies a keymap name that is selected for any
          operations by the current command.

     If a keymap selection is required and none of the options above are
     used, the 'main' keymap is used.  Some operations do not permit a
     keymap to be selected, namely:

     -l
          List all existing keymap names; if any arguments are given,
          list just those keymaps.

          If the -L option is also used, list in the form of bindkey
          commands to create or link the keymaps.  'bindkey -lL main'
          shows which keymap is linked to 'main', if any, and hence if
          the standard emacs or vi emulation is in effect.  This option
          does not show the .safe keymap because it cannot be created in
          that fashion; however, neither is 'bindkey -lL .safe' reported
          as an error, it simply outputs nothing.

     -d
          Delete all existing keymaps and reset to the default state.

     -D KEYMAP ...
          Delete the named KEYMAPs.

     -A OLD-KEYMAP NEW-KEYMAP
          Make the NEW-KEYMAP name an alias for OLD-KEYMAP, so that both
          names refer to the same keymap.  The names have equal
          standing; if either is deleted, the other remains.  If there
          is already a keymap with the NEW-KEYMAP name, it is deleted.

     -N NEW-KEYMAP [ OLD-KEYMAP ]
          Create a new keymap, named NEW-KEYMAP.  If a keymap already
          has that name, it is deleted.  If an OLD-KEYMAP name is given,
          the new keymap is initialized to be a duplicate of it,
          otherwise the new keymap will be empty.

     To use a newly created keymap, it should be linked to main.  Hence
     the sequence of commands to create and use a new keymap 'mymap'
     initialized from the emacs keymap (which remains unchanged) is:

          bindkey -N mymap emacs
          bindkey -A mymap main

     Note that while 'bindkey -A NEWMAP main' will work when NEWMAP is
     emacs or viins, it will not work for vicmd, as switching from vi
     insert to command mode becomes impossible.

     The following operations act on the 'main' keymap if no keymap
     selection option was given:

     -m
          Add the built-in set of meta-key bindings to the selected
          keymap.  Only keys that are unbound or bound to self-insert
          are affected.

     -r IN-STRING ...
          Unbind the specified IN-STRINGs in the selected keymap.  This
          is exactly equivalent to binding the strings to undefined-key.

          When -R is also used, interpret the IN-STRINGs as ranges.

          When -p is also used, the IN-STRINGs specify prefixes.  Any
          binding that has the given IN-STRING as a prefix, not
          including the binding for the IN-STRING itself, if any, will
          be removed.  For example,

               bindkey -rpM viins '^['

          will remove all bindings in the vi-insert keymap beginning
          with an escape character (probably cursor keys), but leave the
          binding for the escape character itself (probably
          vi-cmd-mode).  This is incompatible with the option -R.

     -s IN-STRING OUT-STRING ...
          Bind each IN-STRING to each OUT-STRING.  When IN-STRING is
          typed, OUT-STRING will be pushed back and treated as input to
          the line editor.  When -R is also used, interpret the
          IN-STRINGs as ranges.

          Note that both IN-STRING and OUT-STRING are subject to the
          same form of interpretation, as described below.

     IN-STRING COMMAND ...
          Bind each IN-STRING to each COMMAND.  When -R is used,
          interpret the IN-STRINGs as ranges.

     [ IN-STRING ]
          List key bindings.  If an IN-STRING is specified, the binding
          of that string in the selected keymap is displayed.
          Otherwise, all key bindings in the selected keymap are
          displayed.  (As a special case, if the -e or -v option is used
          alone, the keymap is _not_ displayed - the implicit linking of
          keymaps is the only thing that happens.)

          When the option -p is used, the IN-STRING must be present.
          The listing shows all bindings which have the given key
          sequence as a prefix, not including any bindings for the key
          sequence itself.

          When the -L option is used, the list is in the form of bindkey
          commands to create the key bindings.

     When the -R option is used as noted above, a valid range consists
     of two characters, with an optional '-' between them.  All
     characters between the two specified, inclusive, are bound as
     specified.

     For either IN-STRING or OUT-STRING, the following escape sequences
     are recognised:

     \a
          bell character
     \b
          backspace
     \e, \E
          escape
     \f
          form feed
     \n
          linefeed (newline)
     \r
          carriage return
     \t
          horizontal tab
     \v
          vertical tab
     \NNN
          character code in octal
     \xNN
          character code in hexadecimal
     \uNNNN
          unicode character code in hexadecimal
     \UNNNNNNNN
          unicode character code in hexadecimal
     \M[-]X
          character with meta bit set
     \C[-]X
          control character
     ^X
          control character

     In all other cases, '\' escapes the following character.  Delete is
     written as '^?'.  Note that '\M^?' and '^\M?' are not the same, and
     that (unlike emacs), the bindings '\M-X' and '\eX' are entirely
     distinct, although they are initialized to the same bindings by
     'bindkey -m'.

vared [ -Aacghe ] [ -p PROMPT ] [ -r RPROMPT ]
      [ -M MAIN-KEYMAP ] [ -m VICMD-KEYMAP ]
      [ -i INIT-WIDGET ] [ -f FINISH-WIDGET ]
      [ -t TTY ] NAME
     The value of the parameter NAME is loaded into the edit buffer, and
     the line editor is invoked.  When the editor exits, NAME is set to
     the string value returned by the editor.  When the -c flag is
     given, the parameter is created if it doesn't already exist.  The
     -a flag may be given with -c to create an array parameter, or the
     -A flag to create an associative array.  If the type of an existing
     parameter does not match the type to be created, the parameter is
     unset and recreated.  The -g flag may be given to suppress warnings
     from the WARN_CREATE_GLOBAL and WARN_NESTED_VAR options.

     If an array or array slice is being edited, separator characters as
     defined in $IFS will be shown quoted with a backslash, as will
     backslashes themselves.  Conversely, when the edited text is split
     into an array, a backslash quotes an immediately following
     separator character or backslash; no other special handling of
     backslashes, or any handling of quotes, is performed.

     Individual elements of existing array or associative array
     parameters may be edited by using subscript syntax on NAME.  New
     elements are created automatically, even without -c.

     If the -p flag is given, the following string will be taken as the
     prompt to display at the left.  If the -r flag is given, the
     following string gives the prompt to display at the right.  If the
     -h flag is specified, the history can be accessed from ZLE. If the
     -e flag is given, typing ^D (Control-D) in an empty buffer causes
     vared to exit immediately with a non-zero return value.

     The -M option gives a keymap to link to the main keymap during
     editing, and the -m option gives a keymap to link to the vicmd
     keymap during editing.  For vi-style editing, this allows a pair of
     keymaps to override viins and vicmd.  For emacs-style editing, only
     -M is normally needed but the -m option may still be used.  On
     exit, the previous keymaps will be restored.

     Vared calls the usual 'zle-line-init' and 'zle-line-finish' hooks
     before and after it takes control.  Using the -i and -f options, it
     is possible to replace these with other custom widgets.

     If '-t TTY' is given, TTY is the name of a terminal device to be
     used instead of the default /dev/tty.  If TTY does not refer to a
     terminal an error is reported.

zle
zle -l [ -L | -a ] [ STRING ... ]
zle -D WIDGET ...
zle -A OLD-WIDGET NEW-WIDGET
zle -N WIDGET [ FUNCTION ]
zle -f FLAG [ FLAG... ]
zle -C WIDGET COMPLETION-WIDGET FUNCTION
zle -R [ -c ] [ DISPLAY-STRING ] [ STRING ... ]
zle -M STRING
zle -U STRING
zle -K KEYMAP
zle -F [ -L | -w ] [ FD [ HANDLER ] ]
zle -I
zle -T [ tc FUNCTION | -r tc | -L ]
zle WIDGET [ -n NUM ] [ -f FLAG ] [ -Nw ] [ -K KEYMAP ] ARGS ...
     The zle builtin performs a number of different actions concerning
     ZLE.

     With no options and no arguments, only the return status will be
     set.  It is zero if ZLE is currently active and widgets could be
     invoked using this builtin command and non-zero otherwise.  Note
     that even if non-zero status is returned, zle may still be active
     as part of the completion system; this does not allow direct calls
     to ZLE widgets.

     Otherwise, which operation it performs depends on its options:

     -l [ -L | -a ] [ STRING ]
          List all existing user-defined widgets.  If the -L option is
          used, list in the form of zle commands to create the widgets.

          When combined with the -a option, all widget names are listed,
          including the builtin ones.  In this case the -L option is
          ignored.

          If at least one STRING is given, and -a is present or -L is
          not used, nothing will be printed.  The return status will be
          zero if all STRINGs are names of existing widgets and non-zero
          if at least one STRING is not a name of a defined widget.  If
          -a is also present, all widget names are used for the
          comparison including builtin widgets, else only user-defined
          widgets are used.

          If at least one STRING is present and the -L option is used,
          user-defined widgets matching any STRING are listed in the
          form of zle commands to create the widgets.

     -D WIDGET ...
          Delete the named WIDGETs.

     -A OLD-WIDGET NEW-WIDGET
          Make the NEW-WIDGET name an alias for OLD-WIDGET, so that both
          names refer to the same widget.  The names have equal
          standing; if either is deleted, the other remains.  If there
          is already a widget with the NEW-WIDGET name, it is deleted.

     -N WIDGET [ FUNCTION ]
          Create a user-defined widget.  If there is already a widget
          with the specified name, it is overwritten.  When the new
          widget is invoked from within the editor, the specified shell
          FUNCTION is called.  If no function name is specified, it
          defaults to the same name as the widget.  For further
          information, see *note Zle Widgets::.

     -f FLAG [ FLAG... ]
          Set various flags on the running widget.  Possible values for
          FLAG are:

          yank for indicating that the widget has yanked text into the
          buffer.  If the widget is wrapping an existing internal
          widget, no further action is necessary, but if it has inserted
          the text manually, then it should also take care to set
          YANK_START and YANK_END correctly.  yankbefore does the same
          but is used when the yanked text appears after the cursor.

          kill for indicating that text has been killed into the
          cutbuffer.  When repeatedly invoking a kill widget, text is
          appended to the cutbuffer instead of replacing it, but when
          wrapping such widgets, it is necessary to call 'zle -f kill'
          to retain this effect.

          vichange for indicating that the widget represents a vi change
          that can be repeated as a whole with 'vi-repeat-change'.  The
          flag should be set early in the function before inspecting the
          value of NUMERIC or invoking other widgets.  This has no
          effect for a widget invoked from insert mode.  If insert mode
          is active when the widget finishes, the change extends until
          next returning to command mode.

     -C WIDGET COMPLETION-WIDGET FUNCTION
          Create a user-defined completion widget named WIDGET.  The
          completion widget will behave like the built-in
          completion-widget whose name is given as COMPLETION-WIDGET.
          To generate the completions, the shell function FUNCTION will
          be called.  For further information, see *note Completion
          Widgets::.

     -R [ -c ] [ DISPLAY-STRING ] [ STRING ... ]
          Redisplay the command line.  If a DISPLAY-STRING is given and
          not empty, this is shown in the status line (immediately below
          the line being edited).

          If the optional STRINGs are given they are listed below the
          prompt in the same way as completion lists are printed.  If no
          STRINGs are given but the -c option is used such a list is
          cleared.

          Note that immediately after returning from running widgets,
          the command line will be redisplayed and the strings displayed
          will be erased.  Therefore, this option is only useful for
          widgets that do not exit immediately after using it.

          This command can safely be called outside user defined
          widgets; if zle is active, the display will be refreshed,
          while if zle is not active, the command has no effect.  In
          this case there will usually be no other arguments.

          The status is zero if zle was active, else one.

     -M STRING
          As with the -R option, the STRING will be displayed below the
          command line; unlike the -R option, the string will not be put
          into the status line but will instead be printed normally
          below the prompt.  This means that the STRING will still be
          displayed after the widget returns (until it is overwritten by
          subsequent commands).

     -U STRING
          This pushes the characters in the STRING onto the input stack
          of ZLE. After the widget currently executed finishes ZLE will
          behave as if the characters in the STRING were typed by the
          user.

          As ZLE uses a stack, if this option is used repeatedly the
          last string pushed onto the stack will be processed first.
          However, the characters in each STRING will be processed in
          the order in which they appear in the string.

     -K KEYMAP
          Selects the keymap named KEYMAP.  An error message will be
          displayed if there is no such keymap.

          This keymap selection affects the interpretation of following
          keystrokes within this invocation of ZLE. Any following
          invocation (e.g., the next command line) will start as usual
          with the 'main' keymap selected.

     -F [ -L | -w ] [ FD [ HANDLER ] ]
          Only available if your system supports one of the 'poll' or
          'select' system calls; most modern systems do.

          Installs HANDLER (the name of a shell function) to handle
          input from file descriptor FD.  Installing a handler for an FD
          which is already handled causes the existing handler to be
          replaced.  Any number of handlers for any number of readable
          file descriptors may be installed.  Note that zle makes no
          attempt to check whether this FD is actually readable when
          installing the handler.  The user must make their own
          arrangements for handling the file descriptor when zle is not
          active.

          When zle is attempting to read data, it will examine both the
          terminal and the list of handled FD's.  If data becomes
          available on a handled FD, zle calls HANDLER with the fd which
          is ready for reading as the first argument.  Under normal
          circumstances this is the only argument, but if an error was
          detected, a second argument provides details: 'hup' for a
          disconnect, 'nval' for a closed or otherwise invalid
          descriptor, or 'err' for any other condition.  Systems that
          support only the 'select' system call always use 'err'.

          If the option -w is also given, the HANDLER is instead a line
          editor widget, typically a shell function made into a widget
          using 'zle -N'.  In that case HANDLER can use all the
          facilities of zle to update the current editing line.  Note,
          however, that as handling FD takes place at a low level
          changes to the display will not automatically appear; the
          widget should call 'zle -R' to force redisplay.  As of this
          writing, widget handlers only support a single argument and
          thus are never passed a string for error state, so widgets
          must be prepared to test the descriptor themselves.

          If either type of handler produces output to the terminal, it
          should call 'zle -I' before doing so (see below).  Handlers
          should not attempt to read from the terminal.

          If no HANDLER is given, but an FD is present, any handler for
          that FD is removed.  If there is none, an error message is
          printed and status 1 is returned.

          If no arguments are given, or the -L option is supplied, a
          list of handlers is printed in a form which can be stored for
          later execution.

          An FD (but not a HANDLER) may optionally be given with the -L
          option; in this case, the function will list the handler if
          any, else silently return status 1.

          Note that this feature should be used with care.  Activity on
          one of the FD's which is not properly handled can cause the
          terminal to become unusable.  Removing an FD handler from
          within a signal trap may cause unpredictable behavior.

          Here is a simple example of using this feature.  A connection
          to a remote TCP port is created using the ztcp command; see
          *note The zsh/net/tcp Module::.  Then a handler is installed
          which simply prints out any data which arrives on this
          connection.  Note that 'select' will indicate that the file
          descriptor needs handling if the remote side has closed the
          connection; we handle that by testing for a failed read.

               if ztcp pwspc 2811; then
                 tcpfd=$REPLY
                 handler() {
                   zle -I
                   local line
                   if ! read -r line <&$1; then
                     # select marks this fd if we reach EOF,
                     # so handle this specially.
                     print "[Read on fd $1 failed, removing.]" >&2
                     zle -F $1
                     return 1
                   fi
                   print -r - $line
                 }
                 zle -F $tcpfd handler
               fi

     -I
          Unusually, this option is most useful outside ordinary widget
          functions, though it may be used within if normal output to
          the terminal is required.  It invalidates the current zle
          display in preparation for output; typically this will be from
          a trap function.  It has no effect if zle is not active.  When
          a trap exits, the shell checks to see if the display needs
          restoring, hence the following will print output in such a way
          as not to disturb the line being edited:

               TRAPUSR1() {
                 # Invalidate zle display
                 [[ -o zle ]] && zle -I
                 # Show output
                 print Hello
               }

          In general, the trap function may need to test whether zle is
          active before using this method (as shown in the example),
          since the zsh/zle module may not even be loaded; if it is not,
          the command can be skipped.

          It is possible to call 'zle -I' several times before control
          is returned to the editor; the display will only be
          invalidated the first time to minimise disruption.

          Note that there are normally better ways of manipulating the
          display from within zle widgets; see, for example, 'zle -R'
          above.

          The returned status is zero if zle was invalidated, even
          though this may have been by a previous call to 'zle -I' or by
          a system notification.  To test if a zle widget may be called
          at this point, execute zle with no arguments and examine the
          return status.

     -T
          This is used to add, list or remove internal transformations
          on the processing performed by the line editor.  It is
          typically used only for debugging or testing and is therefore
          of little interest to the general user.

          'zle -T TRANSFORMATION FUNC' specifies that the given
          TRANSFORMATION (see below) is effected by shell function FUNC.

          'zle -Tr TRANSFORMATION' removes the given TRANSFORMATION if
          it was present (it is not an error if none was).

          'zle -TL' can be used to list all transformations currently in
          operation.

          Currently the only transformation is tc.  This is used instead
          of outputting termcap codes to the terminal.  When the
          transformation is in operation the shell function is passed
          the termcap code that would be output as its first argument;
          if the operation required a numeric argument, that is passed
          as a second argument.  The function should set the shell
          variable REPLY to the transformed termcap code.  Typically
          this is used to produce some simply formatted version of the
          code and optional argument for debugging or testing.  Note
          that this transformation is not applied to other non-printing
          characters such as carriage returns and newlines.

     WIDGET [ -n NUM ] [ -f FLAG ] [ -Nw ] [ -K KEYMAP ] ARGS ...
          Invoke the specified WIDGET.  This can only be done when ZLE
          is active; normally this will be within a user-defined widget.

          With the options -n and -N, the current numeric argument will
          be saved and then restored after the call to WIDGET; '-n NUM'
          sets the numeric argument temporarily to NUM, while '-N' sets
          it to the default, i.e.  as if there were none.

          With the option -K, KEYMAP will be used as the current keymap
          during the execution of the widget.  The previous keymap will
          be restored when the widget exits.

          Normally, calling a widget in this way does not set the
          special parameter WIDGET and related parameters, so that the
          environment appears as if the top-level widget called by the
          user were still active.  With the option -w, WIDGET and
          related parameters are set to reflect the widget being
          executed by the zle call.

          Normally, when WIDGET returns the special parameter LASTWIDGET
          will point to it.  This can be inhibited by passing the option
          -f nolast.

          Any further arguments will be passed to the widget; note that
          as standard argument handling is performed, any general
          argument list should be preceded by --.  If it is a shell
          function, these are passed down as positional parameters; for
          builtin widgets it is up to the widget in question what it
          does with them.  Currently arguments are only handled by the
          incremental-search commands, the history-search-forward and
          -backward and the corresponding functions prefixed by vi-, and
          by universal-argument.  No error is flagged if the command
          does not use the arguments, or only uses some of them.

          The return status reflects the success or failure of the
          operation carried out by the widget, or if it is a
          user-defined widget the return status of the shell function.

          A non-zero return status causes the shell to beep when the
          widget exits, unless the BEEP options was unset or the widget
          was called via the zle command.  Thus if a user defined widget
          requires an immediate beep, it should call the beep widget
          directly.


File: zsh.info,  Node: Zle Widgets,  Next: User-Defined Widgets,  Prev: Zle Builtins,  Up: Zsh Line Editor

18.4 Zle Widgets
================

All actions in the editor are performed by 'widgets'.  A widget's job is
simply to perform some small action.  The ZLE commands that key
sequences in keymaps are bound to are in fact widgets.  Widgets can be
user-defined or built in.

The standard widgets built into ZLE are listed in *note Standard
Widgets::.  Other built-in widgets can be defined by other modules (see
*note Zsh Modules::).  Each built-in widget has two names: its normal
canonical name, and the same name preceded by a '.'.  The '.' name is
special: it can't be rebound to a different widget.  This makes the
widget available even when its usual name has been redefined.

User-defined widgets are defined using 'zle -N', and implemented as
shell functions.  When the widget is executed, the corresponding shell
function is executed, and can perform editing (or other) actions.  It is
recommended that user-defined widgets should not have names starting
with '.'.


File: zsh.info,  Node: User-Defined Widgets,  Next: Standard Widgets,  Prev: Zle Widgets,  Up: Zsh Line Editor

18.5 User-Defined Widgets
=========================

User-defined widgets, being implemented as shell functions, can execute
any normal shell command.  They can also run other widgets (whether
built-in or user-defined) using the zle builtin command.  The standard
input of the function is redirected from /dev/null to prevent external
commands from unintentionally blocking ZLE by reading from the terminal,
but read -k or read -q can be used to read characters.  Finally, they
can examine and edit the ZLE buffer being edited by reading and setting
the special parameters described below.

These special parameters are always available in widget functions, but
are not in any way special outside ZLE. If they have some normal value
outside ZLE, that value is temporarily inaccessible, but will return
when the widget function exits.  These special parameters in fact have
local scope, like parameters created in a function using local.

Inside completion widgets and traps called while ZLE is active, these
parameters are available read-only.

Note that the parameters appear as local to any ZLE widget in which they
appear.  Hence if it is desired to override them this needs to be done
within a nested function:

     widget-function() {
       # $WIDGET here refers to the special variable
       # that is local inside widget-function
       () {
          # This anonymous nested function allows WIDGET
          # to be used as a local variable.  The -h
          # removes the special status of the variable.
          local -h WIDGET
       }
     }

BUFFER (scalar)
     The entire contents of the edit buffer.  If it is written to, the
     cursor remains at the same offset, unless that would put it outside
     the buffer.

BUFFERLINES (integer)
     The number of screen lines needed for the edit buffer currently
     displayed on screen (i.e.  without any changes to the preceding
     parameters done after the last redisplay); read-only.

CONTEXT (scalar)
     The context in which zle was called to read a line; read-only.  One
     of the values:

     start
          The start of a command line (at prompt PS1).

     cont
          A continuation to a command line (at prompt PS2).

     select
          In a select loop (at prompt PS3).

     vared
          Editing a variable in vared.

CURSOR (integer)
     The offset of the cursor, within the edit buffer.  This is in the
     range 0 to $#BUFFER, and is by definition equal to $#LBUFFER.
     Attempts to move the cursor outside the buffer will result in the
     cursor being moved to the appropriate end of the buffer.

CUTBUFFER (scalar)
     The last item cut using one of the 'kill-' commands; the string
     which the next yank would insert in the line.  Later entries in the
     kill ring are in the array killring.  Note that the command 'zle
     copy-region-as-kill STRING' can be used to set the text of the cut
     buffer from a shell function and cycle the kill ring in the same
     way as interactively killing text.

HISTNO (integer)
     The current history number.  Setting this has the same effect as
     moving up or down in the history to the corresponding history line.
     An attempt to set it is ignored if the line is not stored in the
     history.  Note this is not the same as the parameter HISTCMD, which
     always gives the number of the history line being added to the main
     shell's history.  HISTNO refers to the line being retrieved within
     zle.

ISEARCHMATCH_ACTIVE (integer)
ISEARCHMATCH_START (integer)
ISEARCHMATCH_END (integer)
     ISEARCHMATCH_ACTIVE indicates whether a part of the BUFFER is
     currently matched by an incremental search pattern.
     ISEARCHMATCH_START and ISEARCHMATCH_END give the location of the
     matched part and are in the same units as CURSOR.  They are only
     valid for reading when ISEARCHMATCH_ACTIVE is non-zero.

     All parameters are read-only.

KEYMAP (scalar)
     The name of the currently selected keymap; read-only.

KEYS (scalar)
     The keys typed to invoke this widget, as a literal string;
     read-only.

KEYS_QUEUED_COUNT (integer)
     The number of bytes pushed back to the input queue and therefore
     available for reading immediately before any I/O is done;
     read-only.  See also PENDING; the two values are distinct.

killring (array)
     The array of previously killed items, with the most recently killed
     first.  This gives the items that would be retrieved by a yank-pop
     in the same order.  Note, however, that the most recently killed
     item is in $CUTBUFFER; $killring shows the array of previous
     entries.

     The default size for the kill ring is eight, however the length may
     be changed by normal array operations.  Any empty string in the
     kill ring is ignored by the yank-pop command, hence the size of the
     array effectively sets the maximum length of the kill ring, while
     the number of non-zero strings gives the current length, both as
     seen by the user at the command line.

LASTABORTEDSEARCH (scalar)
     The last search string used by an interactive search that was
     aborted by the user (status 3 returned by the search widget).

LASTSEARCH (scalar)
     The last search string used by an interactive search; read-only.
     This is set even if the search failed (status 0, 1 or 2 returned by
     the search widget), but not if it was aborted by the user.

LASTWIDGET (scalar)
     The name of the last widget that was executed; read-only.

LBUFFER (scalar)
     The part of the buffer that lies to the left of the cursor
     position.  If it is assigned to, only that part of the buffer is
     replaced, and the cursor remains between the new $LBUFFER and the
     old $RBUFFER.

MARK (integer)
     Like CURSOR, but for the mark.  With vi-mode operators that wait
     for a movement command to select a region of text, setting MARK
     allows the selection to extend in both directions from the initial
     cursor position.

NUMERIC (integer)
     The numeric argument.  If no numeric argument was given, this
     parameter is unset.  When this is set inside a widget function,
     builtin widgets called with the zle builtin command will use the
     value assigned.  If it is unset inside a widget function, builtin
     widgets called behave as if no numeric argument was given.

PENDING (integer)
     The number of bytes pending for input, i.e.  the number of bytes
     which have already been typed and can immediately be read.  On
     systems where the shell is not able to get this information, this
     parameter will always have a value of zero.  Read-only.  See also
     KEYS_QUEUED_COUNT; the two values are distinct.

PREBUFFER (scalar)
     In a multi-line input at the secondary prompt, this read-only
     parameter contains the contents of the lines before the one the
     cursor is currently in.

PREDISPLAY (scalar)
     Text to be displayed before the start of the editable text buffer.
     This does not have to be a complete line; to display a complete
     line, a newline must be appended explicitly.  The text is reset on
     each new invocation (but not recursive invocation) of zle.

POSTDISPLAY (scalar)
     Text to be displayed after the end of the editable text buffer.
     This does not have to be a complete line; to display a complete
     line, a newline must be prepended explicitly.  The text is reset on
     each new invocation (but not recursive invocation) of zle.

RBUFFER (scalar)
     The part of the buffer that lies to the right of the cursor
     position.  If it is assigned to, only that part of the buffer is
     replaced, and the cursor remains between the old $LBUFFER and the
     new $RBUFFER.

REGION_ACTIVE (integer)
     Indicates if the region is currently active.  It can be assigned 0
     or 1 to deactivate and activate the region respectively.  A value
     of 2 activates the region in line-wise mode with the highlighted
     text extending for whole lines only; see *note Character
     Highlighting::.

region_highlight (array)
     Each element of this array may be set to a string that describes
     highlighting for an arbitrary region of the command line that will
     take effect the next time the command line is redisplayed.
     Highlighting of the non-editable parts of the command line in
     PREDISPLAY and POSTDISPLAY are possible, but note that the P flag
     is needed for character indexing to include PREDISPLAY.

     Each string consists of the following whitespace-separated parts:

        • Optionally, a 'P' to signify that the start and end offset
          that follow include any string set by the PREDISPLAY special
          parameter; this is needed if the predisplay string itself is
          to be highlighted.  Whitespace between the 'P' and the start
          offset is optional.
        • A start offset in the same units as CURSOR.
        • An end offset in the same units as CURSOR.
        • A highlight specification in the same format as used for
          contexts in the parameter zle_highlight, see *note Character
          Highlighting::; for example, standout or fg=red,bold.
        • Optionally, a string of the form 'memo=TOKEN'.  The TOKEN
          consists of everything between the '=' and the next
          whitespace, comma, NUL, or the end of the string.  The TOKEN
          is preserved verbatim but not parsed in any way.

          Plugins may use this to identify array elements they have
          added: for example, a plugin might set TOKEN to its (the
          plugin's) name and then use 'region_highlight=(
          ${region_highlight:#*memo=TOKEN} )' in order to remove array
          elements it have added.

          (This example uses the '${NAME:#PATTERN}' array-grepping
          syntax described in *note Parameter Expansion::.)

     For example,

          region_highlight=("P0 20 bold memo=foobar")

     specifies that the first twenty characters of the text including
     any predisplay string should be highlighted in bold.

     Note that the effect of region_highlight is not saved and
     disappears as soon as the line is accepted.

     Note that zsh 5.8 and older do not support the 'memo=TOKEN' field
     and may misparse the third (highlight specification) field when a
     memo is given.

     The final highlighting on the command line depends on both
     region_highlight and zle_highlight; see *note Character
     Highlighting:: for details.

registers (associative array)
     The contents of each of the vi register buffers.  These are
     typically set using vi-set-buffer followed by a delete, change or
     yank command.

SUFFIX_ACTIVE (integer)
SUFFIX_START (integer)
SUFFIX_END (integer)
     SUFFIX_ACTIVE indicates whether an auto-removable completion suffix
     is currently active.  SUFFIX_START and SUFFIX_END give the location
     of the suffix and are in the same units as CURSOR.  They are only
     valid for reading when SUFFIX_ACTIVE is non-zero.

     All parameters are read-only.

UNDO_CHANGE_NO (integer)
     A number representing the state of the undo history.  The only use
     of this is passing as an argument to the undo widget in order to
     undo back to the recorded point.  Read-only.

UNDO_LIMIT_NO (integer)
     A number corresponding to an existing change in the undo history;
     compare UNDO_CHANGE_NO.  If this is set to a value greater than
     zero, the undo command will not allow the line to be undone beyond
     the given change number.  It is still possible to use 'zle undo
     CHANGE' in a widget to undo beyond that point; in that case, it
     will not be possible to undo at all until UNDO_LIMIT_NO is reduced.
     Set to 0 to disable the limit.

     A typical use of this variable in a widget function is as follows
     (note the additional function scope is required):

          () {
            local UNDO_LIMIT_NO=$UNDO_CHANGE_NO
            # Perform some form of recursive edit.
          }

WIDGET (scalar)
     The name of the widget currently being executed; read-only.

WIDGETFUNC (scalar)
     The name of the shell function that implements a widget defined
     with either zle -N or zle -C.  In the former case, this is the
     second argument to the zle -N command that defined the widget, or
     the first argument if there was no second argument.  In the latter
     case this is the third argument to the zle -C command that defined
     the widget.  Read-only.

WIDGETSTYLE (scalar)
     Describes the implementation behind the completion widget currently
     being executed; the second argument that followed zle -C when the
     widget was defined.  This is the name of a builtin completion
     widget.  For widgets defined with zle -N this is set to the empty
     string.  Read-only.

YANK_ACTIVE (integer)
YANK_START (integer)
YANK_END (integer)
     YANK_ACTIVE indicates whether text has just been yanked (pasted)
     into the buffer.  YANK_START and YANK_END give the location of the
     pasted text and are in the same units as CURSOR.  They are only
     valid for reading when YANK_ACTIVE is non-zero.  They can also be
     assigned by widgets that insert text in a yank-like fashion, for
     example wrappers of bracketed-paste.  See also zle -f.

     YANK_ACTIVE is read-only.

ZLE_RECURSIVE (integer)
     Usually zero, but incremented inside any instance of
     recursive-edit.  Hence indicates the current recursion level.

     ZLE_RECURSIVE is read-only.

ZLE_STATE (scalar)
     Contains a set of space-separated words that describe the current
     zle state.

     Currently, the states shown are the insert mode as set by the
     overwrite-mode or vi-replace widgets and whether history commands
     will visit imported entries as controlled by the set-local-history
     widget.  The string contains 'insert' if characters to be inserted
     on the command line move existing characters to the right or
     'overwrite' if characters to be inserted overwrite existing
     characters.  It contains 'localhistory' if only local history
     commands will be visited or 'globalhistory' if imported history
     commands will also be visited.

     The substrings are sorted in alphabetical order so that if you want
     to test for two specific substrings in a future-proof way, you can
     do match by doing:

          if [[ $ZLE_STATE == *globalhistory*insert* ]]; then ...; fi

18.5.1 Special Widgets
----------------------

There are a few user-defined widgets which are special to the shell.  If
they do not exist, no special action is taken.  The environment provided
is identical to that for any other editing widget.

zle-isearch-exit
     Executed at the end of incremental search at the point where the
     isearch prompt is removed from the display.  See zle-isearch-update
     for an example.

zle-isearch-update
     Executed within incremental search when the display is about to be
     redrawn.  Additional output below the incremental search prompt can
     be generated by using 'zle -M' within the widget.  For example,

          zle-isearch-update() { zle -M "Line $HISTNO"; }
          zle -N zle-isearch-update

     Note the line output by 'zle -M' is not deleted on exit from
     incremental search.  This can be done from a zle-isearch-exit
     widget:

          zle-isearch-exit() { zle -M ""; }
          zle -N zle-isearch-exit

zle-line-pre-redraw
     Executed whenever the input line is about to be redrawn, providing
     an opportunity to update the region_highlight array.

zle-line-init
     Executed every time the line editor is started to read a new line
     of input.  The following example puts the line editor into vi
     command mode when it starts up.

          zle-line-init() { zle -K vicmd; }
          zle -N zle-line-init

     (The command inside the function sets the keymap directly; it is
     equivalent to zle vi-cmd-mode.)

zle-line-finish
     This is similar to zle-line-init but is executed every time the
     line editor has finished reading a line of input.

zle-history-line-set
     Executed when the history line changes.

zle-keymap-select
     Executed every time the keymap changes, i.e.  the special parameter
     KEYMAP is set to a different value, while the line editor is
     active.  Initialising the keymap when the line editor starts does
     not cause the widget to be called.

     The value $KEYMAP within the function reflects the new keymap.  The
     old keymap is passed as the sole argument.

     This can be used for detecting switches between the vi command
     (vicmd) and insert (usually main) keymaps.

