Provided by: zsh-common_5.8.1-1_all bug

NAME

       zshmodules - zsh loadable modules

DESCRIPTION

       Some  optional  parts of zsh are in modules, separate from the core of the shell.  Each of
       these modules may be linked in to the shell at build time, or can  be  dynamically  linked
       while  the shell is running if the installation supports this feature.  Modules are linked
       at runtime with the zmodload command, see zshbuiltins(1).

       The modules that are bundled with the zsh distribution are:

       zsh/attr
              Builtins for manipulating extended attributes (xattr).

       zsh/cap
              Builtins for manipulating POSIX.1e (POSIX.6) capability (privilege) sets.

       zsh/clone
              A builtin that can clone a running shell onto another terminal.

       zsh/compctl
              The compctl builtin for controlling completion.

       zsh/complete
              The basic completion code.

       zsh/complist
              Completion listing extensions.

       zsh/computil
              A module with utility builtins needed  for  the  shell  function  based  completion
              system.

       zsh/curses
              curses windowing commands

       zsh/datetime
              Some date/time commands and parameters.

       zsh/db/gdbm
              Builtins for managing associative array parameters tied to GDBM databases.

       zsh/deltochar
              A ZLE function duplicating EMACS' zap-to-char.

       zsh/example
              An example of how to write a module.

       zsh/files
              Some basic file manipulation commands as builtins.

       zsh/langinfo
              Interface to locale information.

       zsh/mapfile
              Access to external files via a special associative array.

       zsh/mathfunc
              Standard scientific functions for use in mathematical evaluations.

       zsh/nearcolor
              Map colours to the nearest colour in the available palette.

       zsh/newuser
              Arrange for files for new users to be installed.

       zsh/parameter
              Access to internal hash tables via special associative arrays.

       zsh/pcre
              Interface to the PCRE library.

       zsh/param/private
              Builtins for managing private-scoped parameters in function context.

       zsh/regex
              Interface to the POSIX regex library.

       zsh/sched
              A builtin that provides a timed execution facility within the shell.

       zsh/net/socket
              Manipulation of Unix domain sockets

       zsh/stat
              A builtin command interface to the stat system call.

       zsh/system
              A builtin interface to various low-level system features.

       zsh/net/tcp
              Manipulation of TCP sockets

       zsh/termcap
              Interface to the termcap database.

       zsh/terminfo
              Interface to the terminfo database.

       zsh/zftp
              A builtin FTP client.

       zsh/zle
              The Zsh Line Editor, including the bindkey and vared builtins.

       zsh/zleparameter
              Access to internals of the Zsh Line Editor via parameters.

       zsh/zprof
              A module allowing profiling for shell functions.

       zsh/zpty
              A builtin for starting a command in a pseudo-terminal.

       zsh/zselect
              Block and return when file descriptors are ready.

       zsh/zutil
              Some utility builtins, e.g. the one for supporting configuration via styles.

THE ZSH/ATTR MODULE

       The  zsh/attr  module  is used for manipulating extended attributes.  The -h option causes
       all commands to operate on symbolic links instead of their targets.  The builtins in  this
       module are:

       zgetattr [ -h ] filename attribute [ parameter ]
              Get  the  extended attribute attribute from the specified filename. If the optional
              argument parameter is given, the attribute is set  on  that  parameter  instead  of
              being printed to stdout.

       zsetattr [ -h ] filename attribute value
              Set the extended attribute attribute on the specified filename to value.

       zdelattr [ -h ] filename attribute
              Remove the extended attribute attribute from the specified filename.

       zlistattr [ -h ] filename [ parameter ]
              List  the  extended  attributes  currently  set  on  the specified filename. If the
              optional argument parameter is given,  the  list  of  attributes  is  set  on  that
              parameter instead of being printed to stdout.

       zgetattr  and  zlistattr  allocate  memory  dynamically.   If  the  attribute  or  list of
       attributes grows between the allocation and the call to get them, they return 2.   On  all
       other  errors, 1 is returned.  This allows the calling function to check for this case and
       retry.

THE ZSH/CAP MODULE

       The zsh/cap module is used for manipulating POSIX.1e (POSIX.6) capability  sets.   If  the
       operating system does not support this interface, the builtins defined by this module will
       do nothing.  The builtins in this module are:

       cap [ capabilities ]
              Change the shell's process capability sets to the specified capabilities, otherwise
              display the shell's current capabilities.

       getcap filename ...
              This  is  a built-in implementation of the POSIX standard utility.  It displays the
              capability sets on each specified filename.

       setcap capabilities filename ...
              This is a built-in implementation of the  POSIX  standard  utility.   It  sets  the
              capability sets on each specified filename to the specified capabilities.

THE ZSH/CLONE MODULE

       The zsh/clone module makes available one builtin command:

       clone tty
              Creates  a forked instance of the current shell, attached to the specified tty.  In
              the new shell, the PID, PPID and TTY special parameters are changed  appropriately.
              $!  is  set  to  zero  in the new shell, and to the new shell's PID in the original
              shell.

              The return status of the builtin is zero in both shells if successful, and non-zero
              on error.

              The target of clone should be an unused terminal, such as an unused virtual console
              or a virtual terminal created by

                     xterm -e sh -c 'trap : INT QUIT TSTP; tty;
                             while :; do sleep 100000000; done'

              Some words of explanation are warranted about this long xterm  command  line:  when
              doing  clone  on  a  pseudo-terminal, some other session ("session" meant as a unix
              session group, or SID) is already owning the terminal. Hence the cloned zsh  cannot
              acquire the pseudo-terminal as a controlling tty. That means two things:

              •      the  job  control  signals  will go to the sh-started-by-xterm process group
                     (that's why we disable INT QUIT and TSTP with trap; otherwise the while loop
                     could get suspended or killed)

              •      the  cloned  shell  will have job control disabled, and the job control keys
                     (control-C, control-\ and control-Z) will not work.

              This does not apply when cloning to an unused vc.

              Cloning to a used (and unprepared) terminal will result in  two  processes  reading
              simultaneously  from  the  same terminal, with input bytes going randomly to either
              process.

              clone is mostly useful as a shell built-in replacement for openvt.

THE ZSH/COMPCTL MODULE

       The zsh/compctl module  makes  available  two  builtin  commands.  compctl,  is  the  old,
       deprecated  way  to  control  completions  for ZLE.  See zshcompctl(1).  The other builtin
       command, compcall can be used in user-defined completion widgets, see zshcompwid(1).

THE ZSH/COMPLETE MODULE

       The zsh/complete module makes available several builtin commands  which  can  be  used  in
       user-defined completion widgets, see zshcompwid(1).

THE ZSH/COMPLIST MODULE

       The  zsh/complist  module  offers  three extensions to completion listings: the ability to
       highlight matches in such a list, the ability to scroll through long lists and a different
       style of menu completion.

   Colored completion listings
       Whenever  one  of  the  parameters  ZLS_COLORS  or ZLS_COLOURS is set and the zsh/complist
       module is loaded or linked into the  shell,  completion  lists  will  be  colored.   Note,
       however,  that  complist  will  not  automatically  be  loaded if it is not linked in:  on
       systems with dynamic loading, `zmodload zsh/complist' is required.

       The parameters ZLS_COLORS and ZLS_COLOURS describe how matches are highlighted.   To  turn
       on  highlighting an empty value suffices, in which case all the default values given below
       will be used.  The format of the value of these parameters is the same as used by the  GNU
       version  of  the  ls  command:  a  colon-separated  list  of  specifications  of  the form
       `name=value'.  The name may be one of the following strings, most of  which  specify  file
       types for which the value will be used.  The strings and their default values are:

       no 0   for normal text (i.e. when displaying something other than a matched file)

       fi 0   for regular files

       di 32  for directories

       ln 36  for  symbolic  links.   If  this  has  the special value target, symbolic links are
              dereferenced and the target file used to determine the display format.

       pi 31  for named pipes (FIFOs)

       so 33  for sockets

       bd 44;37
              for block devices

       cd 44;37
              for character devices

       or none
              for a symlink to nonexistent file (default is the value defined for ln)

       mi none
              for a non-existent file (default is  the  value  defined  for  fi);  this  code  is
              currently not used

       su 37;41
              for files with setuid bit set

       sg 30;43
              for files with setgid bit set

       tw 30;42
              for world writable directories with sticky bit set

       ow 34;43
              for world writable directories without sticky bit set

       sa none
              for  files  with  an  associated  suffix  alias; this is only tested after specific
              suffixes, as described below

       st 37;44
              for directories with sticky bit set but not world writable

       ex 35  for executable files

       lc \e[ for the left code (see below)

       rc m   for the right code

       tc 0   for the character  indicating  the  file  type   printed  after  filenames  if  the
              LIST_TYPES option is set

       sp 0   for the spaces printed after matches to align the next column

       ec none
              for the end code

       Apart  from  these strings, the name may also be an asterisk (`*') followed by any string.
       The value given for such a string will be used for all files  whose  name  ends  with  the
       string.   The  name  may  also  be  an  equals  sign  (`=')  followed  by  a  pattern; the
       EXTENDED_GLOB option will be turned on for evaluation of the pattern.  The value given for
       this  pattern  will  be used for all matches (not just filenames) whose display string are
       matched by the pattern.  Definitions for  the  form  with  the  leading  equal  sign  take
       precedence  over the values defined for file types, which in turn take precedence over the
       form with the leading asterisk (file extensions).

       The leading-equals form also allows different parts of the displayed strings to be colored
       differently.   For  this,  the  pattern  has  to use the `(#b)' globbing flag and pairs of
       parentheses surrounding the parts of the strings that are to be colored  differently.   In
       this case the value may consist of more than one color code separated by equal signs.  The
       first code will be used for all parts for which no explicit  code  is  specified  and  the
       following  codes  will  be  used for the parts matched by the sub-patterns in parentheses.
       For example, the specification `=(#b)(?)*(?)=0=3=7' will be used for all matches which are
       at  least  two  characters long and will use the code `3' for the first character, `7' for
       the last character and `0' for the rest.

       All three forms of name may be preceded by a pattern in parentheses.  If  this  is  given,
       the  value  will be used only for matches in groups whose names are matched by the pattern
       given in the parentheses.  For example, `(g*)m*=43' highlights all matches beginning  with
       `m' in groups whose names  begin with `g' using the color code `43'.  In case of the `lc',
       `rc', and `ec' codes, the group pattern is ignored.

       Note also that all patterns are tried in the order in which they appear in  the  parameter
       value  until  the  first  one matches which is then used.  Patterns may be matched against
       completions, descriptions (possibly with spaces appended for padding), or lines consisting
       of a completion followed by a description.  For consistent coloring it may be necessary to
       use more than one pattern or a pattern with backreferences.

       When printing a match, the code prints the value of lc, the value for the file-type or the
       last  matching  specification  with  a `*', the value of rc, the string to display for the
       match itself, and then the value of ec if that is defined or the values of lc, no, and  rc
       if ec is not defined.

       The  default  values  are  ISO  6429  (ANSI) compliant and can be used on vt100 compatible
       terminals such as xterms.  On monochrome terminals the default values will have no visible
       effect.   The  colors function from the contribution can be used to get associative arrays
       containing  the  codes  for  ANSI  terminals  (see  the  section  `Other   Functions'   in
       zshcontrib(1)).  For example, after loading colors, one could use `$color[red]' to get the
       code for foreground color red and `$color[bg-green]' for the  code  for  background  color
       green.

       If  the  completion system invoked by compinit is used, these parameters should not be set
       directly because the system controls them itself.  Instead, the list-colors  style  should
       be used (see the section `Completion System Configuration' in zshcompsys(1)).

   Scrolling in completion listings
       To  enable scrolling through a completion list, the LISTPROMPT parameter must be set.  Its
       value will be used as the prompt; if it is the empty string,  a  default  prompt  will  be
       used.   The  value  may  contain  escapes of the form `%x'.  It supports the escapes `%B',
       `%b', `%S', `%s', `%U', `%u', `%F', `%f', `%K', `%k' and  `%{...%}'  used  also  in  shell
       prompts  as well as three pairs of additional sequences: a `%l' or `%L' is replaced by the
       number of the last line shown and the total number of lines in the form `number/total';  a
       `%m'  or  `%M' is replaced with the number of the last match shown and the total number of
       matches; and `%p' or `%P' is replaced with `Top', `Bottom' or the position  of  the  first
       line  shown in percent of the total number of lines, respectively.  In each of these cases
       the form with the uppercase letter will be replaced with a string of fixed  width,  padded
       to the right with spaces, while the lowercase form will not be padded.

       If the parameter LISTPROMPT is set, the completion code will not ask if the list should be
       shown.  Instead it immediately starts  displaying  the  list,  stopping  after  the  first
       screenful,  showing  the  prompt  at  the bottom, waiting for a keypress after temporarily
       switching to the listscroll keymap.  Some of the zle  functions  have  a  special  meaning
       while scrolling lists:

       send-break
              stops listing discarding the key pressed

       accept-line, down-history, down-line-or-history
       down-line-or-search, vi-down-line-or-history
              scrolls forward one line

       complete-word, menu-complete, expand-or-complete
       expand-or-complete-prefix, menu-complete-or-expand
              scrolls forward one screenful

       accept-search
              stop listing but take no other action

       Every  other  character stops listing and immediately processes the key as usual.  Any key
       that is not bound in the listscroll keymap or that is bound to undefined-key is looked  up
       in the keymap currently selected.

       As  for  the  ZLS_COLORS and ZLS_COLOURS parameters, LISTPROMPT should not be set directly
       when using the shell function based completion system.   Instead,  the  list-prompt  style
       should be used.

   Menu selection
       The zsh/complist module also offers an alternative style of selecting matches from a list,
       called menu selection, which can be used if the shell is set up  to  return  to  the  last
       prompt   after   showing   a   completion  list  (see  the  ALWAYS_LAST_PROMPT  option  in
       zshoptions(1)).

       Menu selection can be invoked directly by the widget menu-select defined by  this  module.
       This  is a standard ZLE widget that can be bound to a key in the usual way as described in
       zshzle(1).

       Alternatively, the parameter MENUSELECT can be set to an integer, which gives the  minimum
       number  of  matches that must be present before menu selection is automatically turned on.
       This second method requires that menu completion be started, either directly from a widget
       such  as menu-complete, or due to one of the options MENU_COMPLETE or AUTO_MENU being set.
       If MENUSELECT is set, but is 0, 1 or empty, menu selection will always be  started  during
       an ambiguous menu completion.

       When using the completion system based on shell functions, the MENUSELECT parameter should
       not be used (like the ZLS_COLORS and ZLS_COLOURS parameters  described  above).   Instead,
       the menu style should be used with the select=... keyword.

       After  menu  selection  is  started, the matches will be listed. If there are more matches
       than fit on the screen, only the first screenful is shown.  The matches to insert into the
       command  line  can be selected from this list.  In the list one match is highlighted using
       the value for ma from the ZLS_COLORS or ZLS_COLOURS parameter.  The default value for this
       is  `7'  which  forces  the  selected  match  to  be  highlighted using standout mode on a
       vt100-compatible terminal.  If  neither  ZLS_COLORS  nor  ZLS_COLOURS  is  set,  the  same
       terminal control sequence as for the `%S' escape in prompts is used.

       If  there are more matches than fit on the screen and the parameter MENUPROMPT is set, its
       value will be shown  below  the  matches.   It  supports  the  same  escape  sequences  as
       LISTPROMPT,  but  the  number of the match or line shown will be that of the one where the
       mark is placed.  If its value is the empty string, a default prompt will be used.

       The MENUSCROLL parameter can be used  to  specify  how  the  list  is  scrolled.   If  the
       parameter  is  unset, this is done line by line, if it is set to `0' (zero), the list will
       scroll half the number of lines of the screen.  If the value is  positive,  it  gives  the
       number  of  lines to scroll and if it is negative, the list will be scrolled the number of
       lines of the screen minus the (absolute) value.

       As for the ZLS_COLORS, ZLS_COLOURS  and  LISTPROMPT  parameters,  neither  MENUPROMPT  nor
       MENUSCROLL  should  be set directly when using the shell function based completion system.
       Instead, the select-prompt and select-scroll styles should be used.

       The completion code sometimes decides not to show all of the matches in the  list.   These
       hidden  matches  are  either  matches  for  which the completion function which added them
       explicitly requested that they not appear in the list (using the -n option of the  compadd
       builtin command) or they are matches which duplicate a string already in the list (because
       they differ only in things like prefixes or suffixes that are not displayed).  In the list
       used  for  menu selection, however, even these matches are shown so that it is possible to
       select them.  To highlight such matches the hi and du capabilities in the  ZLS_COLORS  and
       ZLS_COLOURS  parameters  are  supported  for  hidden matches of the first and second kind,
       respectively.

       Selecting matches is done by moving the mark around  using  the  zle  movement  functions.
       When  not all matches can be shown on the screen at the same time, the list will scroll up
       and down when crossing the top or bottom line.  The following zle functions  have  special
       meaning  during  menu  selection.   Note  that  the following always perform the same task
       within the menu selection map and cannot be replaced by user defined widgets, nor can  the
       set of functions be extended:

       accept-line, accept-search
              accept  the  current  match  and leave menu selection (but do not cause the command
              line to be accepted)

       send-break
              leaves menu selection and restores the previous contents of the command line

       redisplay, clear-screen
              execute their normal function without leaving menu selection

       accept-and-hold, accept-and-menu-complete
              accept the currently inserted match and continue selection allowing to  select  the
              next match to insert into the line

       accept-and-infer-next-history
              accepts  the current match and then tries completion with menu selection again;  in
              the case of files this allows one to select a directory and immediately attempt  to
              complete  files in it;  if there are no matches, a message is shown and one can use
              undo to go back to completion on the previous level, every other  key  leaves  menu
              selection  (including  the  other  zle functions which are otherwise special during
              menu selection)

       undo   removes matches inserted during the menu selection by one of  the  three  functions
              before

       down-history, down-line-or-history
       vi-down-line-or-history,  down-line-or-search
              moves the mark one line down

       up-history, up-line-or-history
       vi-up-line-or-history, up-line-or-search
              moves the mark one line up

       forward-char, vi-forward-char
              moves the mark one column right

       backward-char, vi-backward-char
              moves the mark one column left

       forward-word, vi-forward-word
       vi-forward-word-end, emacs-forward-word
              moves the mark one screenful down

       backward-word, vi-backward-word, emacs-backward-word
              moves the mark one screenful up

       vi-forward-blank-word, vi-forward-blank-word-end
              moves the mark to the first line of the next group of matches

       vi-backward-blank-word
              moves the mark to the last line of the previous group of matches

       beginning-of-history
              moves the mark to the first line

       end-of-history
              moves the mark to the last line

       beginning-of-buffer-or-history, beginning-of-line
       beginning-of-line-hist, vi-beginning-of-line
              moves the mark to the leftmost column

       end-of-buffer-or-history, end-of-line
       end-of-line-hist, vi-end-of-line
              moves the mark to the rightmost column

       complete-word, menu-complete, expand-or-complete
       expand-or-complete-prefix, menu-expand-or-complete
              moves the mark to the next match

       reverse-menu-complete
              moves the mark to the previous match

       vi-insert
              this  toggles  between  normal  and  interactive mode; in interactive mode the keys
              bound to self-insert and self-insert-unmeta insert into  the  command  line  as  in
              normal  editing  mode  but  without  leaving  menu  selection; after each character
              completion is tried again and the list changes to contain only the new matches; the
              completion  widgets  make the longest unambiguous string be inserted in the command
              line and undo and backward-delete-char go back to the previous set of matches

       history-incremental-search-forward
       history-incremental-search-backward
              this starts incremental searches in the list  of  completions  displayed;  in  this
              mode,  accept-line  only  leaves  incremental search, going back to the normal menu
              selection mode

       All movement functions wrap around at the edges; any other zle function not listed  leaves
       menu  selection  and  executes that function.  It is possible to make widgets in the above
       list do the same by using the form of the widget with a `.' in front.   For  example,  the
       widget  `.accept-line'  has  the effect of leaving menu selection and accepting the entire
       command line.

       During this selection the widget uses the keymap menuselect.  Any key that is not  defined
       in  this  keymap  or  that  is bound to undefined-key is looked up in the keymap currently
       selected.  This is used to ensure that the  most  important  keys  used  during  selection
       (namely  the  cursor  keys, return, and TAB) have sensible defaults.  However, keys in the
       menuselect keymap can  be  modified  directly  using  the  bindkey  builtin  command  (see
       zshmodules(1)). For example, to make the return key leave menu selection without accepting
       the match currently selected one could call

              bindkey -M menuselect '^M' send-break

       after loading the zsh/complist module.

THE ZSH/COMPUTIL MODULE

       The zsh/computil module adds several builtin  commands  that  are  used  by  some  of  the
       completion  functions in the completion system based on shell functions (see zshcompsys(1)
       ).  Except for compquote these builtin commands are very specialised  and  thus  not  very
       interesting  when  writing  your  own  completion  functions.   In  summary, these builtin
       commands are:

       comparguments
              This is used by the _arguments  function  to  do  the  argument  and  command  line
              parsing.   Like  compdescribe  it has an option -i to do the parsing and initialize
              some internal state and various options to access the state information  to  decide
              what should be completed.

       compdescribe
              This is used by the _describe function to build the displays for the matches and to
              get the strings to add as matches with their options.  On the first call one of the
              options  -i  or  -I  should  be supplied as the first argument.  In the first case,
              display strings without the descriptions will be generated, in the second case, the
              string  used  to  separate the matches from their descriptions must be given as the
              second argument and the descriptions (if any) will be shown.  All  other  arguments
              are like the definition arguments to _describe itself.

              Once  compdescribe  has  been called with either the -i or the -I option, it can be
              repeatedly called with the -g option and  the  names  of  four  parameters  as  its
              arguments.   This  will  step  through  the different sets of matches and store the
              value of compstate[list] in the first scalar, the options for compadd in the second
              array,  the  matches  in  the  third  array, and the strings to be displayed in the
              completion listing in the fourth array.  The arrays may then be directly  given  to
              compadd to register the matches with the completion code.

       compfiles
              Used  by the _path_files function to optimize complex recursive filename generation
              (globbing).  It does three things.  With the -p and -P options it builds  the  glob
              patterns  to  use,  including  the paths already handled and trying to optimize the
              patterns with respect to the  prefix  and  suffix  from  the  line  and  the  match
              specification  currently  used.   The  -i  option  does the directory tests for the
              ignore-parents style and the -r option tests if a component for some of the matches
              are equal to the string on the line and removes all other matches if that is true.

       compgroups
              Used  by  the  _tags  function to implement the internals of the group-order style.
              This only takes its arguments as names of completion groups and creates the  groups
              for  it (all six types: sorted and unsorted, both without removing duplicates, with
              removing all duplicates and with removing consecutive duplicates).

       compquote [ -p ] names ...
              There may be reasons to write completion functions that have  to  add  the  matches
              using  the  -Q  option  to  compadd  and  perform  quoting  themselves.  Instead of
              interpreting the first character of the all_quotes key  of  the  compstate  special
              association and using the q flag for parameter expansions, one can use this builtin
              command.  The arguments are the names of scalar or array parameters and the  values
              of  these  parameters are quoted as needed for the innermost quoting level.  If the
              -p option is given, quoting is done as if there is some prefix before the values of
              the parameters, so that a leading equal sign will not be quoted.

              The return status is non-zero in case of an error and zero otherwise.

       comptags
       comptry
              These implement the internals of the tags mechanism.

       compvalues
              Like comparguments, but for the _values function.

THE ZSH/CURSES MODULE

       The zsh/curses module makes available one builtin command and various parameters.

   Builtin
       zcurses init
       zcurses end
       zcurses addwin targetwin nlines ncols begin_y begin_x [ parentwin ]
       zcurses delwin targetwin
       zcurses refresh [ targetwin ... ]
       zcurses touch targetwin ...
       zcurses move targetwin new_y new_x
       zcurses clear targetwin [ redraw | eol | bot ]
       zcurses position targetwin array
       zcurses char targetwin character
       zcurses string targetwin string
       zcurses border targetwin border
       zcurses attr targetwin [ [+|-]attribute | fg_col/bg_col ] [...]
       zcurses bg targetwin [ [+|-]attribute | fg_col/bg_col | @char ] [...]
       zcurses scroll targetwin [ on | off | [+|-]lines ]
       zcurses input targetwin [ param [ kparam [ mparam ] ] ]
       zcurses mouse [ delay num | [+|-]motion ]
       zcurses timeout targetwin intval
       zcurses querychar targetwin [ param ]
       zcurses resize height width [ endwin | nosave | endwin_nosave ]
              Manipulate  curses  windows.   All  uses  of  this  command  should be bracketed by
              `zcurses init' to initialise use of curses, and `zcurses end' to end  it;  omitting
              `zcurses end' can cause the terminal to be in an unwanted state.

              The  subcommand  addwin  creates a window with nlines lines and ncols columns.  Its
              upper left corner will be placed at row begin_y and column begin_x of  the  screen.
              targetwin  is  a  string  and  refers to the name of a window that is not currently
              assigned.  Note in particular the curses convention  that  vertical  values  appear
              before horizontal values.

              If  addwin  is  given  an  existing window as the final argument, the new window is
              created as a subwindow of parentwin.  This differs from an ordinary new  window  in
              that  the  memory  of  the  window  contents  is  shared  with the parent's memory.
              Subwindows must be deleted before their  parent.   Note  that  the  coordinates  of
              subwindows are relative to the screen, not the parent, as with other windows.

              Use  the  subcommand  delwin to delete a window created with addwin.  Note that end
              does not implicitly delete windows, and that delwin does not erase the screen image
              of the window.

              The  window  corresponding  to  the full visible screen is called stdscr; it always
              exists after `zcurses init' and cannot be delete with delwin.

              The subcommand refresh will refresh window targetwin; this is necessary to make any
              pending changes (such as characters you have prepared for output with char) visible
              on the screen.  refresh without an argument causes the screen  to  be  cleared  and
              redrawn.  If multiple windows are given, the screen is updated once at the end.

              The  subcommand  touch  marks  the targetwins listed as changed.  This is necessary
              before refreshing windows if a window that was in front of  another  window  (which
              may be stdscr) is deleted.

              The subcommand move moves the cursor position in targetwin to new coordinates new_y
              and new_x.  Note that the subcommand string (but not the subcommand char)  advances
              the cursor position over the characters added.

              The  subcommand clear erases the contents of targetwin.  One (and no more than one)
              of three options may be specified.  With the option redraw, in  addition  the  next
              refresh  of  targetwin will cause the screen to be cleared and repainted.  With the
              option eol, targetwin is only cleared to the end of the current cursor line.   With
              the  option  bot,  targetwin is cleared to the end of the window, i.e everything to
              the right and below the cursor is cleared.

              The subcommand position writes various positions associated with targetwin into the
              array named array.  These are, in order:
              -      The y and x coordinates of the cursor relative to the top left of targetwin
              -      The y and x coordinates of the top left of targetwin on the screen
              -      The size of targetwin in y and x dimensions.

              Outputting characters and strings are achieved by char and string respectively.

              To  draw a border around window targetwin, use border.  Note that the border is not
              subsequently handled specially:  in other words, the border  is  simply  a  set  of
              characters  output  at  the  edge  of the window.  Hence it can be overwritten, can
              scroll off the window, etc.

              The subcommand attr will set targetwin's attributes or foreground/background  color
              pair  for any successive character output.  Each attribute given on the line may be
              prepended by a + to set or a - to unset that attribute; +  is  assumed  if  absent.
              The attributes supported are blink, bold, dim, reverse, standout, and underline.

              Each fg_col/bg_col attribute (to be read as `fg_col on bg_col') sets the foreground
              and background  color  for  character  output.   The  color  default  is  sometimes
              available  (in  particular if the library is ncurses), specifying the foreground or
              background color with which the terminal started.  The color  pair  default/default
              is  always  available.  To  use  more  than  the  8 named colors (red, green, etc.)
              construct the fg_col/bg_col pairs where fg_col and bg_col are decimal integers, e.g
              128/200.  The maximum color value is 254 if the terminal supports 256 colors.

              bg  overrides  the color and other attributes of all characters in the window.  Its
              usual use is to set the background initially, but it will overwrite the  attributes
              of  any  characters  at  the  time when it is called.  In addition to the arguments
              allowed with attr, an argument @char specifies a character to be shown in otherwise
              blank  areas  of  the  window.   Owing  to  limitations  of curses this cannot be a
              multibyte character  (use  of  ASCII  characters  only  is  recommended).   As  the
              specified  set  of  attributes override the existing background, turning attributes
              off in the arguments is not useful, though this does not cause an error.

              The subcommand scroll can be used with on or off to enabled or disable scrolling of
              a  window  when  the  cursor would otherwise move below the window due to typing or
              output.  It can also be used with a positive or  negative  integer  to  scroll  the
              window  up  or  down  the given number of lines without changing the current cursor
              position (which therefore appears to move in the opposite direction relative to the
              window).   In  the  second case, if scrolling is off it is temporarily turned on to
              allow the window to be scrolled.

              The subcommand input reads a single character from the window  without  echoing  it
              back.   If param is supplied the character is assigned to the parameter param, else
              it is assigned to the parameter REPLY.

              If both param and kparam are supplied, the key is read in `keypad' mode.   In  this
              mode  special  keys such as function keys and arrow keys return the name of the key
              in the parameter kparam.  The key names are the macros defined in the  curses.h  or
              ncurses.h with the prefix `KEY_' removed; see also the description of the parameter
              zcurses_keycodes below.  Other keys cause a value to be set in param as before.  On
              a  successful  return  only one of param or kparam contains a non-empty string; the
              other is set to an empty string.

              If mparam is also supplied, input attempts to handle mouse  input.   This  is  only
              available  with the ncurses library; mouse handling can be detected by checking for
              the exit status of `zcurses mouse' with no arguments.  If a mouse button is clicked
              (or  double-  or  triple-clicked,  or pressed or released with a configurable delay
              from being clicked) then kparam is set to the string MOUSE, and mparam is set to an
              array consisting of the following elements:
              -      An  identifier  to discriminate different input devices; this is only rarely
                     useful.
              -      The x, y and z coordinates of the mouse click relative to the  full  screen,
                     as  three elements in that order (i.e. the y coordinate is, unusually, after
                     the x coordinate).  The z coordinate is only available  for  a  few  unusual
                     input devices and is otherwise set to zero.
              -      Any  events that occurred as separate items; usually there will be just one.
                     An  event  consists  of  PRESSED,  RELEASED,  CLICKED,   DOUBLE_CLICKED   or
                     TRIPLE_CLICKED  followed  immediately (in the same element) by the number of
                     the button.
              -      If the shift key was pressed, the string SHIFT.
              -      If the control key was pressed, the string CTRL.
              -      If the alt key was pressed, the string ALT.

              Not all mouse events may be passed through to the terminal  window;  most  terminal
              emulators  handle  some  mouse  events  themselves.   Note  that the ncurses manual
              implies that using input both with and without mouse handling may cause  the  mouse
              cursor to appear and disappear.

              The  subcommand  mouse  can be used to configure the use of the mouse.  There is no
              window argument; mouse options are  global.   `zcurses  mouse'  with  no  arguments
              returns  status  0  if  mouse  handling is possible, else status 1.  Otherwise, the
              possible arguments (which may be combined on the same command line) are as follows.
              delay  num  sets the maximum delay in milliseconds between press and release events
              to be considered as a click; the value 0 disables click resolution, and the default
              is  one  sixth of a second.  motion proceeded by an optional `+' (the default) or -
              turns on or off reporting of mouse  motion  in  addition  to  clicks,  presses  and
              releases,  which are always reported.  However, it appears reports for mouse motion
              are not currently implemented.

              The subcommand timeout specifies a timeout value  for  input  from  targetwin.   If
              intval is negative, `zcurses input' waits indefinitely for a character to be typed;
              this is the default.  If intval is zero, `zcurses input'  returns  immediately;  if
              there  is typeahead it is returned, else no input is done and status 1 is returned.
              If intval is positive, `zcurses input' waits intval milliseconds for input  and  if
              there is none at the end of that period returns status 1.

              The subcommand querychar queries the character at the current cursor position.  The
              return values are stored in the array named param if supplied, else  in  the  array
              reply.  The first value is the character (which may be a multibyte character if the
              system supports them); the second is the color  pair  in  the  usual  fg_col/bg_col
              notation,  or  0  if  color is not supported.  Any attributes other than color that
              apply to the character, as set with  the  subcommand  attr,  appear  as  additional
              elements.

              The  subcommand  resize resizes stdscr and all windows to given dimensions (windows
              that stick out from the new dimensions are resized  down).  The  underlying  curses
              extension  (resize_term call) can be unavailable. To verify, zeroes can be used for
              height and width. If the result of the subcommand is 0, resize_term is available (2
              otherwise).  Tests  show  that  resizing  can  be  normally accomplished by calling
              zcurses end and zcurses refresh. The resize subcommand is provided for versatility.
              Multiple  system  configurations  have  been  checked  and  zcurses end and zcurses
              refresh are still needed for correct terminal state after resize.  To  invoke  them
              with  resize,  use  endwin argument.  Using nosave argument will cause new terminal
              state to not be saved internally by zcurses. This is also provided for  versatility
              and should normally be not needed.

   Parameters
       ZCURSES_COLORS
              Readonly  integer.  The maximum number of colors the terminal supports.  This value
              is initialised by the curses library and is not  available  until  the  first  time
              zcurses init is run.

       ZCURSES_COLOR_PAIRS
              Readonly  integer.   The  maximum  number  of color pairs fg_col/bg_col that may be
              defined in `zcurses attr' commands; note this limit applies to all color pairs that
              have been used whether or not they are currently active.  This value is initialised
              by the curses library and is not available until the first  time  zcurses  init  is
              run.

       zcurses_attrs
              Readonly  array.   The attributes supported by zsh/curses; available as soon as the
              module is loaded.

       zcurses_colors
              Readonly array.  The colors supported by  zsh/curses;  available  as  soon  as  the
              module is loaded.

       zcurses_keycodes
              Readonly  array.   The values that may be returned in the second parameter supplied
              to `zcurses input' in the order in which they are  defined  internally  by  curses.
              Not all function keys are listed, only F0; curses reserves space for F0 up to F63.

       zcurses_windows
              Readonly  array.   The  current  list  of  windows, i.e. all windows that have been
              created with `zcurses addwin' and not removed with `zcurses delwin'.

THE ZSH/DATETIME MODULE

       The zsh/datetime module makes available one builtin command:

       strftime [ -s scalar ] format [ epochtime [ nanoseconds ] ]
       strftime -r [ -q ] [ -s scalar ] format timestring
              Output the date in the format specified.  With no  epochtime,  the  current  system
              date/time  is  used;  optionally,  epochtime  may  be used to specify the number of
              seconds since the epoch, and nanoseconds may additionally be used  to  specify  the
              number  of  nanoseconds past the second (otherwise that number is assumed to be 0).
              See strftime(3) for details.  The zsh extensions described in the section EXPANSION
              OF PROMPT SEQUENCES in zshmisc(1) are also available.

              -q     Run  quietly;  suppress  printing  of  all  error  messages described below.
                     Errors for invalid epochtime values are always printed.

              -r     With the  option  -r  (reverse),  use  format  to  parse  the  input  string
                     timestring  and  output  the  number of seconds since the epoch at which the
                     time occurred.  The parsing is implemented by the system function  strptime;
                     see  strptime(3).   This means that zsh format extensions are not available,
                     but for reverse lookup they are not required.

                     In most implementations of  strftime  any  timezone  in  the  timestring  is
                     ignored  and  the  local timezone declared by the TZ environment variable is
                     used; other parameters are set to zero if not present.

                     If timestring does not match format the command returns status 1 and  prints
                     an  error  message.   If timestring matches format but not all characters in
                     timestring were used, the conversion  succeeds  but  also  prints  an  error
                     message.

                     If  either  of  the  system  functions  strptime or mktime is not available,
                     status 2 is returned and an error message is printed.

              -s scalar
                     Assign the date string (or epoch time in seconds if -r is given)  to  scalar
                     instead of printing it.

              Note  that  depending  on  the  system's  declared integral time type, strftime may
              produce incorrect results for epoch times greater than 2147483647 which corresponds
              to 2038-01-19 03:14:07 +0000.

       The zsh/datetime module makes available several parameters; all are readonly:

       EPOCHREALTIME
              A  floating  point  value  representing the number of seconds since the epoch.  The
              notional accuracy is to nanoseconds if the clock_gettime call is available  and  to
              microseconds  otherwise,  but  in  practice  the range of double precision floating
              point and shell scheduling latencies may be significant effects.

       EPOCHSECONDS
              An integer value representing the number of seconds since the epoch.

       epochtime
              An array value containing the number of  seconds  since  the  epoch  in  the  first
              element  and the remainder of the time since the epoch in nanoseconds in the second
              element.  To ensure the two elements are consistent the array should be  copied  or
              otherwise  referenced  as  a  single  substitution before the values are used.  The
              following idiom may be used:

                     for secs nsecs in $epochtime; do
                       ...
                     done

THE ZSH/DB/GDBM MODULE

       The zsh/db/gdbm module is used to create  "tied"  associative  arrays  that  interface  to
       database  files.   If  the  GDBM  interface is not available, the builtins defined by this
       module will report an error.  This module is also intended as  a  prototype  for  creating
       additional  database  interfaces, so the ztie builtin may move to a more generic module in
       the future.

       The builtins in this module are:

       ztie -d db/gdbm -f filename [ -r ] arrayname
              Open the GDBM database identified  by  filename  and,  if  successful,  create  the
              associative  array arrayname linked to the file.  To create a local tied array, the
              parameter must first be declared, so commands similar to  the  following  would  be
              executed inside a function scope:

                     local -A sampledb
                     ztie -d db/gdbm -f sample.gdbm sampledb

              The  -r  option opens the database file for reading only, creating a parameter with
              the readonly attribute.  Without this option, using `ztie' on a file for which  the
              user  does  not  have  write  permission is an error.  If writable, the database is
              opened synchronously so fields changed in  arrayname  are  immediately  written  to
              filename.

              Changes  to the file modes filename after it has been opened do not alter the state
              of arrayname, but `typeset -r arrayname' works as expected.

       zuntie [ -u ] arrayname ...
              Close the  GDBM  database  associated  with  each  arrayname  and  then  unset  the
              parameter.   The  -u  option forces an unset of parameters made readonly with `ztie
              -r'.

              This happens automatically if the parameter is explicitly unset or its local  scope
              (function)  ends.   Note  that a readonly parameter may not be explicitly unset, so
              the only way to unset a global parameter created with `ztie -r' is to  use  `zuntie
              -u'.

       zgdbmpath parametername
              Put path to database file assigned to parametername into REPLY scalar.

       zgdbm_tied
              Array holding names of all tied parameters.

       The fields of an associative array tied to GDBM are neither cached nor otherwise stored in
       memory, they are read from or written to  the  database  on  each  reference.   Thus,  for
       example,  the  values  in  a  readonly array may be changed by a second writer of the same
       database file.

THE ZSH/DELTOCHAR MODULE

       The zsh/deltochar module makes available two ZLE functions:

       delete-to-char
              Read a character from the keyboard, and delete from the cursor position up  to  and
              including  the  next (or, with repeat count n, the nth) instance of that character.
              Negative repeat counts mean delete backwards.

       zap-to-char
              This behaves like delete-to-char, except that the final occurrence of the character
              itself is not deleted.

THE ZSH/EXAMPLE MODULE

       The zsh/example module makes available one builtin command:

       example [ -flags ] [ args ... ]
              Displays the flags and arguments it is invoked with.

       The purpose of the module is to serve as an example of how to write a module.

THE ZSH/FILES MODULE

       The  zsh/files  module  makes  available  some  common  commands  for file manipulation as
       builtins; these commands are probably not needed for many normal  situations  but  can  be
       useful  in  emergency recovery situations with constrained resources.  The commands do not
       implement all features now required by relevant standards committees.

       For all commands, a variant beginning zf_ is  also  available  and  loaded  automatically.
       Using  the  features  capability  of zmodload will let you load only those names you want.
       Note that it's possible to load only  the  builtins  with  zsh-specific  names  using  the
       following command:

              zmodload -m -F zsh/files b:zf_\*

       The commands loaded by default are:

       chgrp [ -hRs ] group filename ...
              Changes  group  of  files  specified.  This is equivalent to chown with a user-spec
              argument of `:group'.

       chmod [ -Rs ] mode filename ...
              Changes mode of files specified.

              The specified mode must be in octal.

              The -R option causes chmod to recursively descend into  directories,  changing  the
              mode of all files in the directory after changing the mode of the directory itself.

              The  -s  option  is  a  zsh  extension to chmod functionality.  It enables paranoid
              behaviour, intended to avoid security problems involving a chmod being tricked into
              affecting  files  other  than the ones intended.  It will refuse to follow symbolic
              links, so that (for example) ``chmod 600 /tmp/foo/passwd'' can't accidentally chmod
              /etc/passwd  if /tmp/foo happens to be a link to /etc.  It will also check where it
              is after leaving directories, so that a recursive chmod of a  deep  directory  tree
              can't  end  up  recursively chmoding /usr as a result of directories being moved up
              the tree.

       chown [ -hRs ] user-spec filename ...
              Changes ownership and group of files specified.

              The user-spec can be in four forms:

              user   change owner to user; do not change group
              user:: change owner to user; do not change group
              user:  change owner to user; change group to user's primary group
              user:group
                     change owner to user; change group to group
              :group do not change owner; change group to group

              In each case, the `:' may instead be a `.'.  The rule is that if  there  is  a  `:'
              then  the  separator is `:', otherwise if there is a `.' then the separator is `.',
              otherwise there is no separator.

              Each of user and group may be either a username (or group name, as appropriate)  or
              a  decimal user ID (group ID).  Interpretation as a name takes precedence, if there
              is an all-numeric username (or group name).

              If the target is a symbolic link, the -h option causes chown to set  the  ownership
              of the link instead of its target.

              The  -R  option  causes chown to recursively descend into directories, changing the
              ownership of all files in  the  directory  after  changing  the  ownership  of  the
              directory itself.

              The  -s  option  is  a  zsh  extension to chown functionality.  It enables paranoid
              behaviour, intended to avoid security problems involving a chown being tricked into
              affecting  files  other  than the ones intended.  It will refuse to follow symbolic
              links, so that (for example) ``chown  luser  /tmp/foo/passwd''  can't  accidentally
              chown  /etc/passwd  if  /tmp/foo  happens to be a link to /etc.  It will also check
              where it is after leaving  directories,  so  that  a  recursive  chown  of  a  deep
              directory  tree  can't  end up recursively chowning /usr as a result of directories
              being moved up the tree.

       ln [ -dfhins ] filename dest
       ln [ -dfhins ] filename ... dir
              Creates hard (or, with -s, symbolic) links.   In  the  first  form,  the  specified
              destination  is  created, as a link to the specified filename.  In the second form,
              each of the filenames is taken in turn, and linked to a pathname in  the  specified
              directory that has the same last pathname component.

              Normally,  ln will not attempt to create hard links to directories.  This check can
              be overridden using the -d option.  Typically  only  the  super-user  can  actually
              succeed  in  creating  hard  links to directories.  This does not apply to symbolic
              links in any case.

              By default, existing files cannot be replaced by links.  The -i option  causes  the
              user  to  be queried about replacing existing files.  The -f option causes existing
              files to be silently deleted, without querying.  -f takes precedence.

              The -h and -n options are identical and both exist for  compatibility;  either  one
              indicates  that  if  the  target  is  a symlink then it should not be dereferenced.
              Typically this is used in combination with -sf so that if an existing  link  points
              to  a  directory  then  it will be removed, instead of followed.  If this option is
              used with multiple filenames and the target  is  a  symbolic  link  pointing  to  a
              directory then the result is an error.

       mkdir [ -p ] [ -m mode ] dir ...
              Creates directories.  With the -p option, non-existing parent directories are first
              created if necessary, and there will be  no  complaint  if  the  directory  already
              exists.   The -m option can be used to specify (in octal) a set of file permissions
              for the created directories, otherwise mode 777 modified by the current umask  (see
              umask(2)) is used.

       mv [ -fi ] filename dest
       mv [ -fi ] filename ... dir
              Moves  files.   In the first form, the specified filename is moved to the specified
              destination.  In the second form, each of the filenames is taken in turn, and moved
              to a pathname in the specified directory that has the same last pathname component.

              By default, the user will be queried before replacing any file that the user cannot
              write to, but writable files will be silently removed.  The -i  option  causes  the
              user  to  be  queried about replacing any existing files.  The -f option causes any
              existing files to be silently deleted, without querying.  -f takes precedence.

              Note that this mv will not move files across devices.  Historical versions  of  mv,
              when  actual  renaming  is  impossible, fall back on copying and removing files; if
              this behaviour is desired, use cp and rm manually.  This may  change  in  a  future
              version.

       rm [ -dfiRrs ] filename ...
              Removes files and directories specified.

              Normally,  rm  will not remove directories (except with the -R or -r options).  The
              -d option causes rm to try removing directories with unlink  (see  unlink(2)),  the
              same  method used for files.  Typically only the super-user can actually succeed in
              unlinking directories in this way.  -d takes precedence over -R and -r.

              By default, the user will be queried before removing any file that the user  cannot
              write  to,  but  writable files will be silently removed.  The -i option causes the
              user to be queried about removing any files.  The -f  option  causes  files  to  be
              silently deleted, without querying, and suppresses all error indications.  -f takes
              precedence.

              The -R and -r options cause rm to recursively descend  into  directories,  deleting
              all files in the directory before removing the directory with the rmdir system call
              (see rmdir(2)).

              The -s option is  a  zsh  extension  to  rm  functionality.   It  enables  paranoid
              behaviour, intended to avoid common security problems involving a root-run rm being
              tricked into removing files other than the ones intended.  It will refuse to follow
              symbolic  links,  so  that  (for example) ``rm /tmp/foo/passwd'' can't accidentally
              remove /etc/passwd if /tmp/foo happens to be a link to /etc.  It  will  also  check
              where  it  is  after  leaving  directories,  so  that a recursive removal of a deep
              directory tree can't end up recursively removing /usr as a  result  of  directories
              being moved up the tree.

       rmdir dir ...
              Removes empty directories specified.

       sync   Calls  the  system call of the same name (see sync(2)), which flushes dirty buffers
              to disk.  It might return before the I/O has actually been completed.

THE ZSH/LANGINFO MODULE

       The zsh/langinfo module makes available one parameter:

       langinfo
              An associative array that maps langinfo elements to their values.

              Your implementation may support a number of the following keys:

              CODESET, D_T_FMT, D_FMT, T_FMT,  RADIXCHAR,  THOUSEP,  YESEXPR,  NOEXPR,  CRNCYSTR,
              ABDAY_{1..7},  DAY_{1..7},  ABMON_{1..12}, MON_{1..12}, T_FMT_AMPM, AM_STR, PM_STR,
              ERA, ERA_D_FMT, ERA_D_T_FMT, ERA_T_FMT, ALT_DIGITS

THE ZSH/MAPFILE MODULE

       The zsh/mapfile module provides one special associative array parameter of the same name.

       mapfile
              This associative array takes as keys the names of files; the resulting value is the
              content  of  the  file.   The value is treated identically to any other text coming
              from a parameter.  The value may also be assigned to, in which  case  the  file  in
              question  is  written  (whether or not it originally existed); or an element may be
              unset,  which  will  delete  the   file   in   question.    For   example,   `vared
              mapfile[myfile]' works as expected, editing the file `myfile'.

              When  the  array  is  accessed  as  a whole, the keys are the names of files in the
              current directory, and the values are empty (to save a huge  overhead  in  memory).
              Thus  ${(k)mapfile}  has  the  same  effect  as the glob operator *(D), since files
              beginning with a dot are not special.  Care must be taken with expressions such  as
              rm ${(k)mapfile}, which will delete every file in the current directory without the
              usual `rm *' test.

              The parameter mapfile may be made read-only; in that case, files referenced may not
              be written or deleted.

              A file may conveniently be read into an array as one line per element with the form
              `array=("${(f@)mapfile[filename]}")'.  The double quotes and the `@' are  necessary
              to  prevent  empty  lines  from  being  removed.  Note that if the file ends with a
              newline, the shell will split on the final newline, generating an additional  empty
              field;         this         can         be        suppressed        by        using
              `array=("${(f@)${mapfile[filename]%$'\n'}}")'.

   Limitations
       Although reading and writing of  the  file  in  question  is  efficiently  handled,  zsh's
       internal  memory  management  may be arbitrarily baroque; however, mapfile is usually very
       much more efficient than anything involving a loop.  Note in  particular  that  the  whole
       contents  of  the  file  will  always  reside physically in memory when accessed (possibly
       multiple times, due to standard parameter substitution operations).  In  particular,  this
       means  handling of sufficiently long files (greater than the machine's swap space, or than
       the range of the pointer type) will be incorrect.

       No errors are printed or flagged for non-existent, unreadable, or unwritable files, as the
       parameter mechanism is too low in the shell execution hierarchy to make this convenient.

       It  is  unfortunate  that the mechanism for loading modules does not yet allow the user to
       specify the name of the shell parameter to be given the special behaviour.

THE ZSH/MATHFUNC MODULE

       The zsh/mathfunc module provides standard mathematical functions for use  when  evaluating
       mathematical  formulae.   The  syntax  agrees  with  normal C and FORTRAN conventions, for
       example,

              (( f = sin(0.3) ))

       assigns the sine of 0.3 to the parameter f.

       Most functions take floating point arguments and return a floating point value.   However,
       any  necessary  conversions from or to integer type will be performed automatically by the
       shell.  Apart from atan with a second argument and the abs, int and float  functions,  all
       functions behave as noted in the manual page for the corresponding C function, except that
       any arguments out of range for the function in question will be detected by the shell  and
       an error reported.

       The  following  functions take a single floating point argument: acos, acosh, asin, asinh,
       atan, atanh, cbrt, ceil, cos, cosh, erf, erfc, exp, expm1, fabs,  floor,  gamma,  j0,  j1,
       lgamma,  log,  log10,  log1p,  log2,  logb,  sin, sinh, sqrt, tan, tanh, y0, y1.  The atan
       function can optionally take a second argument, in  which  case  it  behaves  like  the  C
       function atan2.  The ilogb function takes a single floating point argument, but returns an
       integer.

       The function signgam takes no arguments, and returns an integer, which is the  C  variable
       of  the  same  name,  as  described  in  gamma(3).   Note that it is therefore only useful
       immediately after a call to gamma or lgamma.  Note also that `signgam()' and `signgam' are
       distinct expressions.

       The  functions  min,  max,  and  sum  are  defined not in this module but in the zmathfunc
       autoloadable function, described in the section `Mathematical Functions' in zshcontrib(1).

       The following  functions  take  two  floating  point  arguments:  copysign,  fmod,  hypot,
       nextafter.

       The following take an integer first argument and a floating point second argument: jn, yn.

       The  following take a floating point first argument and an integer second argument: ldexp,
       scalb.

       The function abs does not convert the type of its single argument; it returns the absolute
       value  of  either  a  floating  point  number  or an integer.  The functions float and int
       convert  their  arguments  into  a  floating  point  or  integer  value  (by   truncation)
       respectively.

       Note that the C pow function is available in ordinary math evaluation as the `**' operator
       and is not provided here.

       The function rand48 is available if your system's mathematical library  has  the  function
       erand48(3).  It returns a pseudo-random floating point number between 0 and 1.  It takes a
       single string optional argument.

       If the argument is not present, the random number seed is initialised by  three  calls  to
       the rand(3) function --- this produces the same random numbers as the next three values of
       $RANDOM.

       If the argument is present, it gives the name of a  scalar  parameter  where  the  current
       random  number  seed  will  be stored.  On the first call, the value must contain at least
       twelve hexadecimal digits (the remainder of the string is ignored), or the  seed  will  be
       initialised in the same manner as for a call to rand48 with no argument.  Subsequent calls
       to rand48(param) will then maintain the seed in the parameter param as a string of  twelve
       hexadecimal  digits,  with  no  base signifier.  The random number sequences for different
       parameters are completely independent, and are also independent from that used by calls to
       rand48 with no argument.

       For example, consider

              print $(( rand48(seed) ))
              print $(( rand48() ))
              print $(( rand48(seed) ))

       Assuming  $seed  does  not exist, it will be initialised by the first call.  In the second
       call, the default seed is initialised; note, however, that because of  the  properties  of
       rand()  there  is a correlation between the seeds used for the two initialisations, so for
       more secure uses, you should generate your own 12-byte seed.  The third  call  returns  to
       the  same sequence of random numbers used in the first call, unaffected by the intervening
       rand48().

THE ZSH/NEARCOLOR MODULE

       The zsh/nearcolor module replaces colours specified  as  hex  triplets  with  the  nearest
       colour  in  the  88 or 256 colour palettes that are widely used by terminal emulators.  By
       default, 24-bit true colour escape codes are generated when colours  are  specified  using
       hex triplets.  These are not supported by all terminals.  The purpose of this module is to
       make it easier to define colour preferences in a form that can  work  across  a  range  of
       terminal emulators.

       Aside  from  the  default colour, the ANSI standard for terminal escape codes provides for
       eight colours. The bright attribute brings  this  to  sixteen.  These  basic  colours  are
       commonly  used in terminal applications due to being widely supported. Expanded 88 and 256
       colour palettes are also common and, while the first sixteen colours vary somewhat between
       terminals  and  configurations,  these  add  a generally consistent and predictable set of
       colours.

       In order to use the zsh/nearcolor module, it only needs to be loaded. Thereafter, whenever
       a  colour  is  specified  using  a  hex  triplet,  it will be compared against each of the
       available colours and the closest will be selected. The first sixteen  colours  are  never
       matched in this process due to being unpredictable.

       It  isn't possible to reliably detect support for true colour in the terminal emulator. It
       is therefore recommended to be selective in loading the zsh/nearcolor module. For example,
       the following checks the COLORTERM environment variable:

              [[ $COLORTERM = *(24bit|truecolor)* ]] || zmodload zsh/nearcolor

       Note  that  some terminals accept the true color escape codes but map them internally to a
       more limited palette in a similar manner to the zsh/nearcolor module.

THE ZSH/NEWUSER MODULE

       The zsh/newuser module is loaded at boot if it is available, the RCS option  is  set,  and
       the  PRIVILEGED  option  is  not  set  (all  three are true by default).  This takes place
       immediately after commands in the global zshenv file (typically /etc/zsh/zshenv), if  any,
       have  been  executed.  If the module is not available it is silently ignored by the shell;
       the module may safely be removed from $MODULE_PATH by  the  administrator  if  it  is  not
       required.

       On  loading,  the  module tests if any of the start-up files .zshenv, .zprofile, .zshrc or
       .zlogin exist in the directory given by the environment variable ZDOTDIR,  or  the  user's
       home  directory  if  that  is  not  set.   The  test is not performed and the module halts
       processing if the shell was in an emulation mode (i.e. had  been  invoked  as  some  other
       shell than zsh).

       If none of the start-up files were found, the module then looks for the file newuser first
       in a sitewide directory, usually the parent directory of the site-functions directory, and
       if  that  is  not  found  the module searches in a version-specific directory, usually the
       parent  of  the  functions  directory  containing  version-specific   functions.    (These
       directories  can be configured when zsh is built using the --enable-site-scriptdir=dir and
       --enable-scriptdir=dir flags to configure, respectively; the defaults are prefix/share/zsh
       and prefix/share/zsh/$ZSH_VERSION where the default prefix is /usr/local.)

       If  the  file  newuser is found, it is then sourced in the same manner as a start-up file.
       The file is expected to contain code to install start-up files for the user,  however  any
       valid shell code will be executed.

       The zsh/newuser module is then unconditionally unloaded.

       Note  that  it is possible to achieve exactly the same effect as the zsh/newuser module by
       adding code to /etc/zsh/zshenv.  The module exists simply  to  allow  the  shell  to  make
       arrangements  for  new  users without the need for intervention by package maintainers and
       system administrators.

       The script supplied with the module invokes the shell function zsh-newuser-install.   This
       may  be  invoked  directly  by the user even if the zsh/newuser module is disabled.  Note,
       however, that if the module is not installed the function will not  be  installed  either.
       The function is documented in the section User Configuration Functions in zshcontrib(1).

THE ZSH/PARAMETER MODULE

       The  zsh/parameter  module  gives  access  to some of the internal hash tables used by the
       shell by defining some special parameters.

       options
              The keys for this associative array are the names of the options that  can  be  set
              and  unset  using the setopt and unsetopt builtins. The value of each key is either
              the string on if the option is currently set, or the string off if  the  option  is
              unset.   Setting  a  key  to  one of these strings is like setting or unsetting the
              option, respectively. Unsetting a key in this array is like setting it to the value
              off.

       commands
              This  array  gives  access  to  the  command  hash table. The keys are the names of
              external commands, the values are the pathnames of the files that would be executed
              when  the command would be invoked. Setting a key in this array defines a new entry
              in this table in the same way as with the hash  builtin.  Unsetting  a  key  as  in
              `unset  "commands[foo]"'  removes the entry for the given key from the command hash
              table.

       functions
              This associative array maps  names  of  enabled  functions  to  their  definitions.
              Setting  a key in it is like defining a function with the name given by the key and
              the body given by the value.  Unsetting  a  key  removes  the  definition  for  the
              function named by the key.

       dis_functions
              Like functions but for disabled functions.

       functions_source
              This  readonly associative array maps names of enabled functions to the name of the
              file containing the source of the function.

              For an autoloaded function that has already been loaded,  or  marked  for  autoload
              with  an absolute path, or that has had its path resolved with `functions -r', this
              is the file found for autoloading, resolved to an absolute path.

              For a function defined within the body of a script or sourced  file,  this  is  the
              name  of  that  file.  In this case, this is the exact path originally used to that
              file, which may be a relative path.

              For any other function, including any  defined  at  an  interactive  prompt  or  an
              autoload  function  whose path has not yet been resolved, this is the empty string.
              However, the hash element is reported as defined just so long as  the  function  is
              present:  the keys to this hash are the same as those to $functions.

       dis_functions_source
              Like functions_source but for disabled functions.

       builtins
              This  associative  array  gives  information  about  the builtin commands currently
              enabled. The keys are the names of the builtin commands and the values  are  either
              `undefined' for builtin commands that will automatically be loaded from a module if
              invoked or `defined' for builtin commands that are already loaded.

       dis_builtins
              Like builtins but for disabled builtin commands.

       reswords
              This array contains the enabled reserved words.

       dis_reswords
              Like reswords but for disabled reserved words.

       patchars
              This array contains the enabled pattern characters.

       dis_patchars
              Like patchars but for disabled pattern characters.

       aliases
              This maps the names of the regular aliases currently enabled to their expansions.

       dis_aliases
              Like aliases but for disabled regular aliases.

       galiases
              Like aliases, but for global aliases.

       dis_galiases
              Like galiases but for disabled global aliases.

       saliases
              Like raliases, but for suffix aliases.

       dis_saliases
              Like saliases but for disabled suffix aliases.

       parameters
              The keys in this associative array  are  the  names  of  the  parameters  currently
              defined.  The  values are strings describing the type of the parameter, in the same
              format used by the t parameter flag, see zshexpn(1) .  Setting or unsetting keys in
              this array is not possible.

       modules
              An  associative  array  giving information about modules. The keys are the names of
              the modules loaded, registered to be autoloaded, or aliased. The value  says  which
              state  the  named module is in and is one of the strings `loaded', `autoloaded', or
              `alias:name', where name is the name the module is aliased to.

              Setting or unsetting keys in this array is not possible.

       dirstack
              A normal array holding the elements of the directory stack. Note that the output of
              the  dirs  builtin  command  includes  one  more  directory,  the  current  working
              directory.

       history
              This associative array maps history  event  numbers  to  the  full  history  lines.
              Although  it  is  presented  as  an  associative  array,  the  array  of all values
              (${history[@]}) is guaranteed to be returned in order from most  recent  to  oldest
              history event, that is, by decreasing history event number.

       historywords
              A  special  array containing the words stored in the history.  These also appear in
              most to least recent order.

       jobdirs
              This associative array maps job numbers to the directories from which the  job  was
              started (which may not be the current directory of the job).

              The keys of the associative arrays are usually valid job numbers, and these are the
              values output with, for example, ${(k)jobdirs}.  Non-numeric job references may  be
              used  when  looking  up  a value; for example, ${jobdirs[%+]} refers to the current
              job.

       jobtexts
              This associative array maps job numbers to the texts of the command lines that were
              used to start the jobs.

              Handling of the keys of the associative array is as described for jobdirs above.

       jobstates
              This  associative  array  gives  information about the states of the jobs currently
              known. The keys are the job  numbers  and  the  values  are  strings  of  the  form
              `job-state:mark:pid=state...'.  The  job-state  gives  the  state  the whole job is
              currently in, one of `running', `suspended', or `done'. The mark  is  `+'  for  the
              current  job, `-' for the previous job and empty otherwise. This is followed by one
              `:pid=state' for every process in the job. The pids are, of course, the process IDs
              and the state describes the state of that process.

              Handling of the keys of the associative array is as described for jobdirs above.

       nameddirs
              This  associative  array  maps the names of named directories to the pathnames they
              stand for.

       userdirs
              This associative array maps user names to the pathnames of their home directories.

       usergroups
              This associative array maps names of system groups of which the current user  is  a
              member  to  the  corresponding group identifiers.  The contents are the same as the
              groups output by the id command.

       funcfiletrace
              This array contains the absolute line numbers and corresponding file names for  the
              point  where  the  current  function, sourced file, or (if EVAL_LINENO is set) eval
              command was called.  The array  is  of  the  same  length  as  funcsourcetrace  and
              functrace, but differs from funcsourcetrace in that the line and file are the point
              of call, not the point of definition, and differs from functrace in that all values
              are  absolute  line  numbers  in  files,  rather  than  relative  to the start of a
              function, if any.

       funcsourcetrace
              This array contains the file names  and  line  numbers  of  the  points  where  the
              functions, sourced files, and (if EVAL_LINENO is set) eval commands currently being
              executed were defined.  The line number is the line where the  `function  name'  or
              `name  ()'  started.   In  the  case  of an autoloaded function  the line number is
              reported as zero.  The format of each element is filename:lineno.

              For functions autoloaded from a file in native zsh format, where only the  body  of
              the function occurs in the file, or for files that have been executed by the source
              or `.' builtins, the trace information is shown as  filename:0,  since  the  entire
              file  is the definition.  The source file name is resolved to an absolute path when
              the function is loaded or the path to it otherwise resolved.

              Most users will be  interested  in  the  information  in  the  funcfiletrace  array
              instead.

       funcstack
              This  array contains the names of the functions, sourced files, and (if EVAL_LINENO
              is set) eval commands. currently being executed. The first element is the  name  of
              the function using the parameter.

              The  standard  shell  array  zsh_eval_context  can be used to determine the type of
              shell construct being executed at  each  depth:  note,  however,  that  is  in  the
              opposite  order,  with  the  most  recent  item  last, and it is more detailed, for
              example including an entry for toplevel, the main shell code being executed  either
              interactively or from a script, which is not present in $funcstack.

       functrace
              This  array contains the names and line numbers of the callers corresponding to the
              functions currently being executed.  The format of  each  element  is  name:lineno.
              Callers  are also shown for sourced files; the caller is the point where the source
              or `.' command was executed.

THE ZSH/PCRE MODULE

       The zsh/pcre module makes some commands available as builtins:

       pcre_compile [ -aimxs ] PCRE
              Compiles a perl-compatible regular expression.

              Option -a will force the  pattern  to  be  anchored.   Option  -i  will  compile  a
              case-insensitive  pattern.  Option -m will compile a multi-line pattern; that is, ^
              and $ will match newlines within the pattern.  Option -x will compile  an  extended
              pattern,  wherein  whitespace  and # comments are ignored.  Option -s makes the dot
              metacharacter match all characters, including those that indicate newline.

       pcre_study
              Studies the previously-compiled PCRE which may result in faster matching.

       pcre_match [ -v var ] [ -a arr ] [ -n offset ] [ -b ] string
              Returns successfully if string matches the previously-compiled PCRE.

              Upon successful match, if the expression captures  substrings  within  parentheses,
              pcre_match  will  set  the array match to those substrings, unless the -a option is
              given, in which case it will set the array arr.  Similarly, the variable MATCH will
              be  set to the entire matched portion of the string, unless the -v option is given,
              in which case the variable var will be set.  No variables are altered if  there  is
              no successful match.  A -n option starts searching for a match from the byte offset
              position in string.  If the -b option is given, the variable ZPCRE_OP will  be  set
              to  an  offset  pair  string,  representing the byte offset positions of the entire
              matched portion within the  string.   For  example,  a  ZPCRE_OP  set  to  "32  45"
              indicates that the matched portion began on byte offset 32 and ended on byte offset
              44.  Here, byte offset position 45 is  the  position  directly  after  the  matched
              portion.   Keep  in  mind  that the byte position isn't necessarily the same as the
              character position when UTF-8 characters  are  involved.   Consequently,  the  byte
              offset  positions  are  only  to  be  relied  on  in  the context of using them for
              subsequent searches on string, using an offset position as an argument  to  the  -n
              option.   This  is  mostly used to implement the "find all non-overlapping matches"
              functionality.

              A simple example of "find all non-overlapping matches":

                     string="The following zip codes: 78884 90210 99513"
                     pcre_compile -m "\d{5}"
                     accum=()
                     pcre_match -b -- $string
                     while [[ $? -eq 0 ]] do
                         b=($=ZPCRE_OP)
                         accum+=$MATCH
                         pcre_match -b -n $b[2] -- $string
                     done
                     print -l $accum

       The zsh/pcre module makes available the following test condition:

       expr -pcre-match pcre
              Matches a string against a perl-compatible regular expression.

              For example,

                     [[ "$text" -pcre-match ^d+$ ]] &&
                     print text variable contains only "d's".

              If the REMATCH_PCRE option is set, the =~ operator is  equivalent  to  -pcre-match,
              and the NO_CASE_MATCH option may be used.  Note that NO_CASE_MATCH never applies to
              the pcre_match builtin, instead use the -i switch of pcre_compile.

THE ZSH/PARAM/PRIVATE MODULE

       The zsh/param/private module is used to create parameters whose scope is  limited  to  the
       current function body, and not to other functions called by the current function.

       This module provides a single autoloaded builtin:

       private [ {+|-}AHUahlprtux ] [ {+|-}EFLRZi [ n ] ] [ name[=value] ... ]
              The   private  builtin  accepts  all  the  same  options  and  arguments  as  local
              (zshbuiltins(1)) except for the `-T' option.   Tied  parameters  may  not  be  made
              private.

              If  used  at  the  top  level  (outside a function scope), private creates a normal
              parameter in the same manner as declare  or  typeset.   A  warning  about  this  is
              printed  if  WARN_CREATE_GLOBAL  is  set  (zshoptions(1)).   Used inside a function
              scope, private creates a local parameter similar to one declared with local, except
              having special properties noted below.

              Special  parameters  which expose or manipulate internal shell state, such as ARGC,
              argv, COLUMNS, LINES, UID, EUID, IFS, PROMPT, RANDOM, SECONDS, etc., cannot be made
              private  unless  the  `-h'  option  is  used  to  hide  the  special meaning of the
              parameter.  This may change in the future.

       As with other typeset equivalents, private is both a  builtin  and  a  reserved  word,  so
       arrays  may be assigned with parenthesized word list name=(value...) syntax.  However, the
       reserved word `private' is not available until zsh/param/private is loaded, so  care  must
       be  taken  with order of execution and parsing for function definitions which use private.
       To compensate for this, the module also adds the option `-P' to  the  `local'  builtin  to
       declare private parameters.

       For  example,  this  construction  fails if zsh/param/private has not yet been loaded when
       `bad_declaration' is defined:
              bad_declaration() {
                zmodload zsh/param/private
                private array=( one two three )
              }

       This construction works because local is already a  keyword,  and  the  module  is  loaded
       before the statement is executed:
              good_declaration() {
                zmodload zsh/param/private
                local -P array=( one two three )
              }

       The following is usable in scripts but may have trouble with autoload:
              zmodload zsh/param/private
              iffy_declaration() {
                private array=( one two three )
              }

       The  private  builtin  may  always  be  used  with scalar assignments and for declarations
       without assignments.

       Parameters declared with private have the following properties:

       •      Within the function body where it is declared, the parameter behaves  as  a  local,
              except as noted above for tied or special parameters.

       •      The  type  of  a parameter declared private cannot be changed in the scope where it
              was declared, even if the parameter is unset.  Thus an array cannot be assigned  to
              a private scalar, etc.

       •      Within  any  other function called by the declaring function, the private parameter
              does NOT hide other parameters of the same name, so for example a global  parameter
              of  the  same name is visible and may be assigned or unset.  This includes calls to
              anonymous functions, although that may also change in the future.

       •      An exported private remains in the environment of inner scopes  but  appears  unset
              for  the  current  shell  in those scopes.  Generally, exporting private parameters
              should be avoided.

       Note that this differs from the static scope defined by compiled languages derived from C,
       in  that  the  a new call to the same function creates a new scope, i.e., the parameter is
       still associated with the call stack rather than with the function definition.  It differs
       from  ksh  `typeset  -S'  because the syntax used to define the function has no bearing on
       whether the parameter scope is respected.

THE ZSH/REGEX MODULE

       The zsh/regex module makes available the following test condition:

       expr -regex-match regex
              Matches a string against a POSIX extended regular expression.  On successful match,
              matched  portion  of  the string will normally be placed in the MATCH variable.  If
              there are any capturing parentheses within the regex, then the match array variable
              will contain those.  If the match is not successful, then the variables will not be
              altered.

              For example,

                     [[ alphabetical -regex-match ^a([^a]+)a([^a]+)a ]] &&
                     print -l $MATCH X $match

              If the option REMATCH_PCRE is not set, then the =~ operator will automatically load
              this module as needed and will invoke the -regex-match operator.

              If  BASH_REMATCH  is  set, then the array BASH_REMATCH will be set instead of MATCH
              and match.

THE ZSH/SCHED MODULE

       The zsh/sched module makes available one builtin command and one parameter.

       sched [-o] [+]hh:mm[:ss] command ...
       sched [-o] [+]seconds command ...
       sched [ -item ]
              Make an entry in the scheduled list of  commands  to  execute.   The  time  may  be
              specified  in  either  absolute  or relative time, and either as hours, minutes and
              (optionally) seconds separated by a colon, or seconds alone.  An absolute number of
              seconds  indicates  the  time since the epoch (1970/01/01 00:00); this is useful in
              combination with the features in the  zsh/datetime  module,  see  the  zsh/datetime
              module entry in zshmodules(1).

              With no arguments, prints the list of scheduled commands.  If the scheduled command
              has the -o flag set, this is shown at the start of the command.

              With the argument `-item', removes the given item from the list.  The numbering  of
              the  list  is continuous and entries are in time order, so the numbering can change
              when entries are added or deleted.

              Commands are executed either immediately before a prompt, or while the shell's line
              editor is waiting for input.  In the latter case it is useful to be able to produce
              output that does not interfere with the line being edited.  Providing the option -o
              causes  the  shell  to  clear  the  command  line  before  the  event and redraw it
              afterwards.  This should be used with any scheduled  event  that  produces  visible
              output  to  the terminal; it is not needed, for example, with output that updates a
              terminal emulator's title bar.

              To effect changes to the editor buffer  when  an  event  executes,  use  the  `zle'
              command  with no arguments to test whether the editor is active, and if it is, then
              use `zle widget' to access the editor via the named widget.

              The sched builtin 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/sched b:sched'.

       zsh_scheduled_events
              A readonly array corresponding to the events scheduled by the sched  builtin.   The
              indices  of  the  array  correspond  to the numbers shown when sched is run with no
              arguments (provided that the KSH_ARRAYS option is not set).  The value of the array
              consists  of  the  scheduled  time in seconds since the epoch (see the section `The
              zsh/datetime Module' for facilities for using this number), followed  by  a  colon,
              followed  by  any  options  (which  may  be  empty  but  will  be preceded by a `-'
              otherwise), followed by a colon, followed by the command to be executed.

              The sched builtin should be used for manipulating the events.  Note that this  will
              have  an  immediate effect on the contents of the array, so that indices may become
              invalid.

THE ZSH/NET/SOCKET MODULE

       The zsh/net/socket module makes available one builtin command:

       zsocket [ -altv ] [ -d fd ] [ args ]
              zsocket is implemented as a builtin  to  allow  full  use  of  shell  command  line
              editing, file I/O, and job control mechanisms.

   Outbound Connections
       zsocket [ -v ] [ -d fd ] filename
              Open  a  new Unix domain connection to filename.  The shell parameter REPLY will be
              set to the file descriptor associated with that connection.  Currently, only stream
              connections are supported.

              If  -d  is  specified, its argument will be taken as the target file descriptor for
              the connection.

              In order to elicit more verbose output, use -v.

              File descriptors can be closed with normal shell syntax when no longer needed,  for
              example:

                     exec {REPLY}>&-

   Inbound Connections
       zsocket -l [ -v ] [ -d fd ] filename
              zsocket  -l  will  open  a socket listening on filename.  The shell parameter REPLY
              will be set to the  file  descriptor  associated  with  that  listener.   The  file
              descriptor remains open in subshells and forked external executables.

              If  -d  is  specified, its argument will be taken as the target file descriptor for
              the connection.

              In order to elicit more verbose output, use -v.

       zsocket -a [ -tv ] [ -d targetfd ] listenfd
              zsocket -a will accept  an  incoming  connection  to  the  socket  associated  with
              listenfd.   The shell parameter REPLY will be set to the file descriptor associated
              with the inbound connection.  The file descriptor remains  open  in  subshells  and
              forked external executables.

              If  -d  is  specified, its argument will be taken as the target file descriptor for
              the connection.

              If -t is specified, zsocket will return  if  no  incoming  connection  is  pending.
              Otherwise it will wait for one.

              In order to elicit more verbose output, use -v.

THE ZSH/STAT MODULE

       The zsh/stat module makes available one builtin command under two possible names:

       zstat [ -gnNolLtTrs ] [ -f fd ] [ -H hash ] [ -A array ] [ -F fmt ]
             [ +element ] [ file ... ]
       stat ...
              The  command  acts  as a front end to the stat system call (see stat(2)).  The same
              command is provided with two names; as the name stat is often used by  an  external
              command  it  is  recommended that only the zstat form of the command is used.  This
              can be arranged by loading the  module  with  the  command  `zmodload  -F  zsh/stat
              b:zstat'.

              If  the  stat call fails, the appropriate system error message printed and status 1
              is returned.  The fields of struct stat give information about the  files  provided
              as arguments to the command.  In addition to those available from the stat call, an
              extra element `link' is provided.  These elements are:

              device The number of the device on which the file resides.

              inode  The unique number of the file on this device (`inode' number).

              mode   The mode of the file; that is, the file's type and access permissions.  With
                     the  -s option, this will be returned as a string corresponding to the first
                     column in the display of the ls -l command.

              nlink  The number of hard links to the file.

              uid    The user ID of the owner of the file.  With the -s option, this is displayed
                     as a user name.

              gid    The  group ID of the file.  With the -s option, this is displayed as a group
                     name.

              rdev   The raw device number.  This is only useful for special devices.

              size   The size of the file in bytes.

              atime
              mtime
              ctime  The  last  access,  modification  and  inode  change  times  of  the   file,
                     respectively,  as  the  number of seconds since midnight GMT on 1st January,
                     1970.  With the -s option, these are printed as strings for the  local  time
                     zone;  the  format can be altered with the -F option, and with the -g option
                     the times are in GMT.

              blksize
                     The number of bytes in one allocation block on the device on which the  file
                     resides.

              block  The number of disk blocks used by the file.

              link   If the file is a link and the -L option is in effect, this contains the name
                     of the file linked to, otherwise it is empty.  Note that if this element  is
                     selected (``zstat +link'') then the -L option is automatically used.

              A particular element may be selected by including its name preceded by a `+' in the
              option list; only one element is allowed.  The element  may  be  shortened  to  any
              unique  set  of  leading characters.  Otherwise, all elements will be shown for all
              files.

              Options:

              -A array
                     Instead of displaying the results on standard  output,  assign  them  to  an
                     array, one struct stat element per array element for each file in order.  In
                     this case neither the name of the element nor the name of the files  appears
                     in  array  unless  the  -t or -n options were given, respectively.  If -t is
                     given, the element name  appears  as  a  prefix  to  the  appropriate  array
                     element;  if  -n is given, the file name appears as a separate array element
                     preceding all the others.  Other formatting options are respected.

              -H hash
                     Similar to -A, but instead assign the values to  hash.   The  keys  are  the
                     elements  listed  above.   If the -n option is provided then the name of the
                     file is included in the hash with key name.

              -f fd  Use the file on file descriptor fd instead of named files; no list  of  file
                     names is allowed in this case.

              -F fmt Supplies  a strftime (see strftime(3)) string for the formatting of the time
                     elements.  The format string supports all of the zsh extensions described in
                     the  section  EXPANSION OF PROMPT SEQUENCES in zshmisc(1).  The -s option is
                     implied.

              -g     Show the time elements in the GMT time zone.  The -s option is implied.

              -l     List the names of the type elements (to  standard  output  or  an  array  as
                     appropriate)  and  return immediately; arguments, and options other than -A,
                     are ignored.

              -L     Perform an lstat (see lstat(2)) rather than a stat  system  call.   In  this
                     case,  if  the file is a link, information about the link itself rather than
                     the target file is returned.  This option  is  required  to  make  the  link
                     element useful.  It's important to note that this is the exact opposite from
                     ls(1), etc.

              -n     Always show the names of files.  Usually these are only shown when output is
                     to standard output and there is more than one file in the list.

              -N     Never show the names of files.

              -o     If  a  raw  file mode is printed, show it in octal, which is more useful for
                     human consumption than the default of  decimal.   A  leading  zero  will  be
                     printed  in  this  case.   Note  that  this does not affect whether a raw or
                     formatted file mode is shown, which is controlled by the -r and -s  options,
                     nor whether a mode is shown at all.

              -r     Print  raw  data (the default format) alongside string data (the -s format);
                     the string data appears in parentheses after the raw data.

              -s     Print mode, uid, gid and the three  time  elements  as  strings  instead  of
                     numbers.  In each case the format is like that of ls -l.

              -t     Always  show  the type names for the elements of struct stat.  Usually these
                     are only shown when output is to standard output and no  individual  element
                     has been selected.

              -T     Never show the type names of the struct stat elements.

THE ZSH/SYSTEM MODULE

       The zsh/system module makes available various builtin commands and parameters.

   Builtins
       syserror [ -e errvar ] [ -p prefix ] [ errno | errname ]
              This  command  prints  out  the error message associated with errno, a system error
              number, followed by a newline to standard error.

              Instead of the error number, a name errname, for example ENOENT, may be used.   The
              set of names is the same as the contents of the array errnos, see below.

              If the string prefix is given, it is printed in front of the error message, with no
              intervening space.

              If errvar is supplied, the entire message, without a newline, is  assigned  to  the
              parameter names errvar and nothing is output.

              A  return  status  of 0 indicates the message was successfully printed (although it
              may not be useful if the error number was out of  the  system's  range),  a  return
              status  of  1  indicates  an  error  in  the  parameters,  and a return status of 2
              indicates the error name was not recognised (no message is printed for this).

       sysopen [ -arw ] [ -m permissions ] [ -o options ]
               -u fd file
              This command opens a file. The -r, -w and -a flags indicate whether the file should
              be  opened  for  reading, writing and appending, respectively. The -m option allows
              the initial permissions to use when creating a file to be specified in octal  form.
              The file descriptor is specified with -u. Either an explicit file descriptor in the
              range 0 to 9 can be specified or a variable name can be given  to  which  the  file
              descriptor number will be assigned.

              The  -o  option  allows  various  system  specific  options  to  be  specified as a
              comma-separated list. The following is a  list  of  possible  options.  Note  that,
              depending on the system, some may not be available.
              cloexec
                     mark  file  to  be  closed  when  other programs are executed (else the file
                     descriptor remains open in subshells and forked external executables)

              create
              creat  create file if it does not exist

              excl   create file, error if it already exists

              noatime
                     suppress updating of the file atime

              nofollow
                     fail if file is a symbolic link

              sync   request that writes wait until data has been physically written

              truncate
              trunc  truncate file to size 0

              To close the file, use one of the following:

                     exec {fd}<&-
                     exec {fd}>&-

       sysread [ -c countvar ] [ -i infd ] [ -o outfd ]
               [ -s bufsize ] [ -t timeout ] [ param ]
              Perform a single system read from file descriptor infd, or  zero  if  that  is  not
              given.   The  result  of the read is stored in param or REPLY if that is not given.
              If countvar is given, the number of bytes read is assigned to the  parameter  named
              by countvar.

              The  maximum  number of bytes read is bufsize or 8192 if that is not given, however
              the command returns as soon as any number of bytes was successfully read.

              If timeout is given, it specifies a timeout in seconds, which may be zero  to  poll
              the  file  descriptor.   This  is  handled  by  the  poll system call if available,
              otherwise the select system call if available.

              If outfd is given, an attempt is made to write all the bytes just read to the  file
              descriptor  outfd.   If  this  fails, because of a system error other than EINTR or
              because of an internal zsh error during  an  interrupt,  the  bytes  read  but  not
              written  are stored in the parameter named by param if supplied (no default is used
              in this case), and the number of bytes read  but  not  written  is  stored  in  the
              parameter  named  by  countvar if that is supplied.  If it was successful, countvar
              contains the full number of bytes transferred, as usual, and param is not set.

              The error EINTR (interrupted system call)  is  handled  internally  so  that  shell
              interrupts are transparent to the caller.  Any other error causes a return.

              The possible return statuses are
              0      At  least  one  byte  of  data  was  successfully  read and, if appropriate,
                     written.

              1      There was an error in the parameters to the command.  This is the only error
                     for which a message is printed to standard error.

              2      There  was an error on the read, or on polling the input file descriptor for
                     a timeout.  The parameter ERRNO gives the error.

              3      Data were successfully read, but there was an error writing them  to  outfd.
                     The parameter ERRNO gives the error.

              4      The  attempt to read timed out.  Note this does not set ERRNO as this is not
                     a system error.

              5      No system error occurred, but zero bytes were read.  This usually  indicates
                     end  of file.  The parameters are set according to the usual rules; no write
                     to outfd is attempted.

       sysseek [ -u fd ] [ -w start|end|current ] offset
              The current file position at which future reads  and  writes  will  take  place  is
              adjusted  to  the  specified  byte  offset.  The  offset  is  evaluated  as  a math
              expression. The -u option allows the file descriptor to be  specified.  By  default
              the  offset is specified relative to the start or the file but, with the -w option,
              it is possible to specify that  the  offset  should  be  relative  to  the  current
              position or the end of the file.

       syswrite [ -c countvar ] [ -o outfd ] data
              The  data (a single string of bytes) are written to the file descriptor outfd, or 1
              if that is not given, using the write system call.  Multiple write  operations  may
              be used if the first does not write all the data.

              If  countvar  is given, the number of byte written is stored in the parameter named
              by countvar; this may not be the full length of data if an error occurred.

              The error EINTR (interrupted  system  call)  is  handled  internally  by  retrying;
              otherwise  an  error  causes  the  command  to  return.   For  example, if the file
              descriptor is set to  non-blocking  output,  an  error  EAGAIN  (on  some  systems,
              EWOULDBLOCK) may result in the command returning early.

              The  return  status  may  be 0 for success, 1 for an error in the parameters to the
              command, or 2 for an error on the write; no error message is printed  in  the  last
              case, but the parameter ERRNO will reflect the error that occurred.

       zsystem flock [ -t timeout ] [ -f var ] [-er] file
       zsystem flock -u fd_expr
              The  builtin  zsystem's  subcommand  flock  performs advisory file locking (via the
              fcntl(2) system call) over the entire contents of the given  file.   This  form  of
              locking  requires  the  processes accessing the file to cooperate; its most obvious
              use is between two instances of the shell itself.

              In the first form the named file, which must already exist, is locked by opening  a
              file  descriptor  to the file and applying a lock to the file descriptor.  The lock
              terminates when the shell process that created the  lock  exits;  it  is  therefore
              often  convenient  to  create  file  locks  within  subshells,  since  the  lock is
              automatically released when the subshell exits.  Note that use of the print builtin
              with the -u option will, as a side effect, release the lock, as will redirection to
              the file in the shell holding the lock.  To work around this use a  subshell,  e.g.
              `(print  message) >> file'.  Status 0 is returned if the lock succeeds, else status
              1.

              In the second form the file descriptor given by the arithmetic  expression  fd_expr
              is  closed,  releasing a lock.  The file descriptor can be queried by using the `-f
              var' form during the lock; on a successful lock, the shell variable var is  set  to
              the  file  descriptor  used  for  locking.   The  lock will be released if the file
              descriptor is closed by  any  other  means,  for  example  using  `exec  {var}>&-';
              however,  the  form described here performs a safety check that the file descriptor
              is in use for file locking.

              By default the shell waits indefinitely for the lock to  succeed.   The  option  -t
              timeout  specifies  a  timeout  for  the lock in seconds; currently this must be an
              integer.  The shell will attempt to lock the file once a second during this period.
              If the attempt times out, status 2 is returned.

              If  the  option -e is given, the file descriptor for the lock is preserved when the
              shell uses exec to start a new process; otherwise it is closed at  that  point  and
              the lock released.

              If  the  option  -r  is  given,  the  lock is only for reading, otherwise it is for
              reading and writing.  The file descriptor is opened accordingly.

       zsystem supports subcommand
              The builtin zsystem's subcommand supports  tests  whether  a  given  subcommand  is
              supported.   It returns status 0 if so, else status 1.  It operates silently unless
              there was a syntax error (i.e. the wrong number of arguments), in which case status
              255 is returned.  Status 1 can indicate one of two things:  subcommand is known but
              not supported by the current operating system, or subcommand is not known (possibly
              because this is an older version of the shell before it was implemented).

   Math Functions
       systell(fd)
              The systell math function returns the current file position for the file descriptor
              passed as an argument.

   Parameters
       errnos A readonly array of the names of errors defined on the system.  These are typically
              macros defined in C by including the system header file errno.h.  The index of each
              name (assuming the option KSH_ARRAYS is unset) corresponds  to  the  error  number.
              Error numbers num before the last known error which have no name are given the name
              Enum in the array.

              Note that aliases for errors are not handled; only the canonical name is used.

       sysparams
              A readonly associative array.  The keys are:

              pid    Returns the process ID of the current process, even in  subshells.   Compare
                     $$, which returns the process ID of the main shell process.

              ppid   Returns  the  process  ID  of  the  parent  of  the current process, even in
                     subshells.  Compare $PPID, which returns the process ID of the parent of the
                     main shell process.

              procsubstpid
                     Returns the process ID of the last process started for process substitution,
                     i.e. the <(...) and >(...) expansions.

THE ZSH/NET/TCP MODULE

       The zsh/net/tcp module makes available one builtin command:

       ztcp [ -acflLtv ] [ -d fd ] [ args ]
              ztcp is implemented as a builtin to allow full use of shell command  line  editing,
              file I/O, and job control mechanisms.

              If ztcp is run with no options, it will output the contents of its session table.

              If  it  is  run with only the option -L, it will output the contents of the session
              table in a format suitable for automatic parsing.  The option is ignored  if  given
              with  a command to open or close a session.  The output consists of a set of lines,
              one per session, each containing the following elements separated by spaces:

              File descriptor
                     The file descriptor in use for the connection.  For normal inbound  (I)  and
                     outbound  (O)  connections  this  may be read and written by the usual shell
                     mechanisms.  However, it should only be close with `ztcp -c'.

              Connection type
                     A letter indicating how the session was created:

                     Z      A session created with the zftp command.

                     L      A connection opened for listening with `ztcp -l'.

                     I      An inbound connection accepted with `ztcp -a'.

                     O      An outbound connection created with `ztcp host ...'.

              The local host
                     This is usually set to  an  all-zero  IP  address  as  the  address  of  the
                     localhost is irrelevant.

              The local port
                     This is likely to be zero unless the connection is for listening.

              The remote host
                     This  is  the fully qualified domain name of the peer, if available, else an
                     IP address.  It  is  an  all-zero  IP  address  for  a  session  opened  for
                     listening.

              The remote port
                     This is zero for a connection opened for listening.

   Outbound Connections
       ztcp [ -v ] [ -d fd ] host [ port ]
              Open a new TCP connection to host.  If the port is omitted, it will default to port
              23.  The connection will be added to the session  table  and  the  shell  parameter
              REPLY will be set to the file descriptor associated with that connection.

              If  -d  is  specified, its argument will be taken as the target file descriptor for
              the connection.

              In order to elicit more verbose output, use -v.

   Inbound Connections
       ztcp -l [ -v ] [ -d fd ] port
              ztcp -l will open a socket listening on TCP port.  The socket will be added to  the
              session  table  and  the  shell  parameter REPLY will be set to the file descriptor
              associated with that listener.

              If -d is specified, its argument will be taken as the target  file  descriptor  for
              the connection.

              In order to elicit more verbose output, use -v.

       ztcp -a [ -tv ] [ -d targetfd ] listenfd
              ztcp  -a  will  accept an incoming connection to the port associated with listenfd.
              The connection will be added to the session table and  the  shell  parameter  REPLY
              will be set to the file descriptor associated with the inbound connection.

              If  -d  is  specified, its argument will be taken as the target file descriptor for
              the connection.

              If -t is specified,  ztcp  will  return  if  no  incoming  connection  is  pending.
              Otherwise it will wait for one.

              In order to elicit more verbose output, use -v.

   Closing Connections
       ztcp -cf [ -v ] [ fd ]
       ztcp -c [ -v ] [ fd ]
              ztcp  -c will close the socket associated with fd.  The socket will be removed from
              the session table.  If fd is not specified,  ztcp  will  close  everything  in  the
              session table.

              Normally,  sockets  registered  by  zftp (see zshmodules(1) ) cannot be closed this
              way.  In order to force such a socket closed, use -f.

              In order to elicit more verbose output, use -v.

   Example
       Here is how to create a TCP connection between two instances of zsh.  We need to  pick  an
       unassigned port; here we use the randomly chosen 5123.

       On host1,
              zmodload zsh/net/tcp
              ztcp -l 5123
              listenfd=$REPLY
              ztcp -a $listenfd
              fd=$REPLY
       The second from last command blocks until there is an incoming connection.

       Now create a connection from host2 (which may, of course, be the same machine):
              zmodload zsh/net/tcp
              ztcp host1 5123
              fd=$REPLY

       Now  on  each host, $fd contains a file descriptor for talking to the other.  For example,
       on host1:
              print This is a message >&$fd
       and on host2:
              read -r line <&$fd; print -r - $line
       prints `This is a message'.

       To tidy up, on host1:
              ztcp -c $listenfd
              ztcp -c $fd
       and on host2
              ztcp -c $fd

THE ZSH/TERMCAP MODULE

       The zsh/termcap module makes available one builtin command:

       echotc cap [ arg ... ]
              Output the termcap  value  corresponding  to  the  capability  cap,  with  optional
              arguments.

       The zsh/termcap module makes available one parameter:

       termcap
              An associative array that maps termcap capability codes to their values.

THE ZSH/TERMINFO MODULE

       The zsh/terminfo module makes available one builtin command:

       echoti cap [ arg ]
              Output  the  terminfo  value corresponding to the capability cap, instantiated with
              arg if applicable.

       The zsh/terminfo module makes available one parameter:

       terminfo
              An associative array that maps terminfo capability names to their values.

THE ZSH/ZFTP MODULE

       The zsh/zftp module makes available one builtin command:

       zftp subcommand [ args ]
              The zsh/zftp  module  is  a  client  for  FTP  (file  transfer  protocol).   It  is
              implemented as a builtin to allow full use of shell command line editing, file I/O,
              and job control mechanisms.  Often,  users  will  access  it  via  shell  functions
              providing  a  more  powerful interface; a set is provided with the zsh distribution
              and is described in zshzftpsys(1).  However, the zftp command is entirely usable in
              its own right.

              All commands consist of the command name zftp followed by the name of a subcommand.
              These are listed below.  The return  status  of  each  subcommand  is  supposed  to
              reflect  the  success or failure of the remote operation.  See a description of the
              variable ZFTP_VERBOSE for more information on how responses from the server may  be
              printed.

   Subcommands
       open host[:port] [ user [ password [ account ] ] ]
              Open a new FTP session to host, which may be the name of a TCP/IP connected host or
              an IP number in the standard  dot  notation.   If  the  argument  is  in  the  form
              host:port,  open a connection to TCP port port instead of the standard FTP port 21.
              This may be the name of a  TCP  service  or  a  number:   see  the  description  of
              ZFTP_PORT below for more information.

              If IPv6 addresses in colon format are used, the host should be surrounded by quoted
              square   brackets   to   distinguish   it    from    the    port,    for    example
              '[fe80::203:baff:fe02:8b56]'.   For  consistency  this is allowed with all forms of
              host.

              Remaining arguments are passed to the login subcommand.  Note that if no  arguments
              beyond  host are supplied, open will not automatically call login.  If no arguments
              at all are supplied, open will use the parameters set by the params subcommand.

              After a successful open, the shell  variables  ZFTP_HOST,  ZFTP_PORT,  ZFTP_IP  and
              ZFTP_SYSTEM are available; see `Variables' below.

       login [ name [ password [ account ] ] ]
       user [ name [ password [ account ] ] ]
              Login  the  user  name with parameters password and account.  Any of the parameters
              can be omitted, and will be read from standard input  if  needed  (name  is  always
              needed).  If standard input is a terminal, a prompt for each one will be printed on
              standard error and password will not be echoed.  If any of the parameters  are  not
              used, a warning message is printed.

              After  a successful login, the shell variables ZFTP_USER, ZFTP_ACCOUNT and ZFTP_PWD
              are available; see `Variables' below.

              This command may be re-issued when a user is already logged in, and the server will
              first be reinitialized for a new user.

       params [ host [ user [ password [ account ] ] ] ]
       params -
              Store  the given parameters for a later open command with no arguments.  Only those
              given on the command line will be remembered.   If  no  arguments  are  given,  the
              parameters  currently  set are printed, although the password will appear as a line
              of stars; the return status is one if no parameters were set, zero otherwise.

              Any of the parameters may be specified as a `?', which may need  to  be  quoted  to
              protect  it  from shell expansion.  In this case, the appropriate parameter will be
              read from stdin as  with  the  login  subcommand,  including  special  handling  of
              password.   If  the  `?'  is  followed  by a string, that is used as the prompt for
              reading the parameter instead of the default message (any necessary punctuation and
              whitespace  should  be included at the end of the prompt).  The first letter of the
              parameter (only) may be quoted with a `\'; hence an argument  "\\$word"  guarantees
              that  the  string from the shell parameter $word will be treated literally, whether
              or not it begins with a `?'.

              If instead a single `-' is given, the existing parameters, if any, are deleted.  In
              that case, calling open with no arguments will cause an error.

              The  list of parameters is not deleted after a close, however it will be deleted if
              the zsh/zftp module is unloaded.

              For example,

                     zftp params ftp.elsewhere.xx juser '?Password for juser: '

              will store the host ftp.elsewhere.xx and the user juser and then  prompt  the  user
              for the corresponding password with the given prompt.

       test   Test  the  connection; if the server has reported that it has closed the connection
              (maybe due to a timeout), return status 2; if no connection was open anyway, return
              status 1; else return status 0.  The test subcommand is silent, apart from messages
              printed by the $ZFTP_VERBOSE mechanism, or error messages if the connection closes.
              There is no network overhead for this test.

              The  test  is only supported on systems with either the select(2) or poll(2) system
              calls; otherwise the message `not supported on this system' is printed instead.

              The test subcommand will  automatically  be  called  at  the  start  of  any  other
              subcommand for the current session when a connection is open.

       cd directory
              Change the remote directory to directory.  Also alters the shell variable ZFTP_PWD.

       cdup   Change  the remote directory to the one higher in the directory tree.  Note that cd
              .. will also work correctly on non-UNIX systems.

       dir [ arg ... ]
              Give a (verbose) listing of the remote directory.  The args are passed directly  to
              the  server. The command's behaviour is implementation dependent, but a UNIX server
              will typically interpret args as arguments to the ls command and with no  arguments
              return the result of `ls -l'. The directory is listed to standard output.

       ls [ arg ... ]
              Give  a  (short) listing of the remote directory.  With no arg, produces a raw list
              of the files in the directory, one per line.  Otherwise,  up  to  vagaries  of  the
              server implementation, behaves similar to dir.

       type [ type ]
              Change  the  type  for  the  transfer to type, or print the current type if type is
              absent.  The allowed values are `A' (ASCII), `I' (Image, i.e. binary),  or  `B'  (a
              synonym for `I').

              The  FTP  default  for a transfer is ASCII.  However, if zftp finds that the remote
              host is a UNIX machine with 8-bit byes,  it  will  automatically  switch  to  using
              binary for file transfers upon open.  This can subsequently be overridden.

              The  transfer  type  is  only  passed  to the remote host when a data connection is
              established; this command involves no network overhead.

       ascii  The same as type A.

       binary The same as type I.

       mode [ S | B ]
              Set the mode type to stream (S) or block (B).  Stream mode is  the  default;  block
              mode is not widely supported.

       remote file ...
       local [ file ... ]
              Print  the  size and last modification time of the remote or local files.  If there
              is more than one item on the list, the name of the  file  is  printed  first.   The
              first number is the file size, the second is the last modification time of the file
              in the format CCYYMMDDhhmmSS consisting of year, month,  date,  hour,  minutes  and
              seconds  in  GMT.   Note  that this format, including the length, is guaranteed, so
              that time strings can be directly compared via the [[ builtin's < and >  operators,
              even if they are too long to be represented as integers.

              Not  all  servers  support  the  commands for retrieving this information.  In that
              case, the remote command will print nothing and  return  status  2,  compared  with
              status 1 for a file not found.

              The local command (but not remote) may be used with no arguments, in which case the
              information comes from examining file descriptor zero.  This is the  same  file  as
              seen by a put command with no further redirection.

       get file ...
              Retrieve all files from the server, concatenating them and sending them to standard
              output.

       put file ...
              For each file, read a file from standard input and send that  to  the  remote  host
              with the given name.

       append file ...
              As  put,  but  if the remote file already exists, data is appended to it instead of
              overwriting it.

       getat file point
       putat file point
       appendat file point
              Versions of get, put and append which will start the transfer at the given point in
              the  remote  file.   This  is  useful  for  appending  to an incomplete local file.
              However, note that this ability is not universally supported by servers (and is not
              quite the behaviour specified by the standard).

       delete file ...
              Delete the list of files on the server.

       mkdir directory
              Create a new directory directory on the server.

       rmdir directory
              Delete the directory directory  on the server.

       rename old-name new-name
              Rename file old-name to new-name on the server.

       site arg ...
              Send  a  host-specific  command to the server.  You will probably only need this if
              instructed by the server to use it.

       quote arg ...
              Send the raw FTP command sequence to the server.  You should be familiar  with  the
              FTP  command  set  as  defined  in  RFC959  before doing this.  Useful commands may
              include STAT and HELP.  Note also the mechanism for returning messages as described
              for  the  variable  ZFTP_VERBOSE  below,  in  particular that all messages from the
              control connection are sent to standard error.

       close
       quit   Close the current data connection.  This unsets  the  shell  parameters  ZFTP_HOST,
              ZFTP_PORT,  ZFTP_IP,  ZFTP_SYSTEM, ZFTP_USER, ZFTP_ACCOUNT, ZFTP_PWD, ZFTP_TYPE and
              ZFTP_MODE.

       session [ sessname ]
              Allows multiple FTP sessions to be used at once.  The name of  the  session  is  an
              arbitrary  string  of characters; the default session is called `default'.  If this
              command is called without an argument, it will list all the current sessions;  with
              an  argument,  it  will  either  switch to the existing session called sessname, or
              create a new session of that name.

              Each session remembers the status of the connection, the set of connection-specific
              shell  parameters  (the same set as are unset when a connection closes, as given in
              the description of close), and  any  user  parameters  specified  with  the  params
              subcommand.   Changing  to  a previous session restores those values; changing to a
              new session initialises them in the same way as if zftp had just been loaded.   The
              name of the current session is given by the parameter ZFTP_SESSION.

       rmsession [ sessname ]
              Delete  a  session; if a name is not given, the current session is deleted.  If the
              current session is deleted, the earliest existing session becomes the  new  current
              session,  otherwise  the  current  session  is  not  changed.  If the session being
              deleted is the only one, a new session called `default' is created and becomes  the
              current  session; note that this is a new session even if the session being deleted
              is also called `default'. It is recommended that  sessions  not  be  deleted  while
              background commands which use zftp are still active.

   Parameters
       The following shell parameters are used by zftp.  Currently none of them are special.

       ZFTP_TMOUT
              Integer.   The  time  in seconds to wait for a network operation to complete before
              returning an error.  If this is not set when the module is loaded, it will be given
              the  default value 60.  A value of zero turns off timeouts.  If a timeout occurs on
              the control connection it will be closed.  Use a larger value if  this  occurs  too
              frequently.

       ZFTP_IP
              Readonly.  The IP address of the current connection in dot notation.

       ZFTP_HOST
              Readonly.  The hostname of the current remote server.  If the host was opened as an
              IP number, ZFTP_HOST contains that instead; this saves  the  overhead  for  a  name
              lookup, as IP numbers are most commonly used when a nameserver is unavailable.

       ZFTP_PORT
              Readonly.   The number of the remote TCP port to which the connection is open (even
              if the port was originally specified as a named  service).   Usually  this  is  the
              standard FTP port, 21.

              In  the  unlikely  event  that your system does not have the appropriate conversion
              functions, this appears in network byte order.  If your  system  is  little-endian,
              the  port then consists of two swapped bytes and the standard port will be reported
              as 5376.  In that case, numeric ports passed to zftp open will also need to  be  in
              this format.

       ZFTP_SYSTEM
              Readonly.  The system type string returned by the server in response to an FTP SYST
              request.  The most interesting case is a string beginning "UNIX  Type:  L8",  which
              ensures maximum compatibility with a local UNIX host.

       ZFTP_TYPE
              Readonly.   The  type  to be used for data transfers , either `A' or `I'.   Use the
              type subcommand to change this.

       ZFTP_USER
              Readonly.  The username currently logged in, if any.

       ZFTP_ACCOUNT
              Readonly.  The account name of the current user,  if  any.   Most  servers  do  not
              require an account name.

       ZFTP_PWD
              Readonly.  The current directory on the server.

       ZFTP_CODE
              Readonly.   The three digit code of the last FTP reply from the server as a string.
              This can still be read after the connection is closed, and is not changed when  the
              current session changes.

       ZFTP_REPLY
              Readonly.   The  last line of the last reply sent by the server.  This can still be
              read after the connection is closed, and is not changed when  the  current  session
              changes.

       ZFTP_SESSION
              Readonly.   The name of the current FTP session; see the description of the session
              subcommand.

       ZFTP_PREFS
              A string of preferences for altering aspects of zftp's behaviour.  Each  preference
              is a single character.  The following are defined:

              P      Passive:   attempt  to make the remote server initiate data transfers.  This
                     is slightly more efficient than sendport mode.  If the letter S occurs later
                     in the string, zftp will use sendport mode if passive mode is not available.

              S      Sendport:   initiate  transfers  by  the  FTP  PORT command.  If this occurs
                     before any P in the string, passive mode will never be attempted.

              D      Dumb:  use only the  bare  minimum  of  FTP  commands.   This  prevents  the
                     variables  ZFTP_SYSTEM  and  ZFTP_PWD  from  being  set,  and  will mean all
                     connections default to ASCII type.  It may prevent ZFTP_SIZE from being  set
                     during a transfer if the server does not send it anyway (many servers do).

              If  ZFTP_PREFS is not set when zftp is loaded, it will be set to a default of `PS',
              i.e. use passive mode if available, otherwise fall back to sendport mode.

       ZFTP_VERBOSE
              A string of digits between 0 and 5 inclusive, specifying which responses  from  the
              server  should  be  printed.   All  responses  go to standard error.  If any of the
              numbers 1 to 5 appear in the string, raw responses from the server with reply codes
              beginning  with  that  digit will be printed to standard error.  The first digit of
              the three digit reply code is defined by RFC959 to correspond to:

              1.     A positive preliminary reply.

              2.     A positive completion reply.

              3.     A positive intermediate reply.

              4.     A transient negative completion reply.

              5.     A permanent negative completion reply.

              It should be noted that, for unknown reasons, the reply  `Service  not  available',
              which  forces  termination  of  a connection, is classified as 421, i.e. `transient
              negative', an interesting interpretation of the word `transient'.

              The code 0 is special:  it indicates that  all  but  the  last  line  of  multiline
              replies  read  from  the  server  will  be printed to standard error in a processed
              format.  By convention, servers use this mechanism for sending information for  the
              user  to  read.  The appropriate reply code, if it matches the same response, takes
              priority.

              If ZFTP_VERBOSE is not set when zftp is loaded, it will be set to the default value
              450,  i.e.,  messages destined for the user and all errors will be printed.  A null
              string is valid and specifies that no messages should be printed.

   Functions
       zftp_chpwd
              If this function is set by the user, it is called every time the directory  changes
              on  the server, including when a user is logged in, or when a connection is closed.
              In the last case, $ZFTP_PWD will be  unset;  otherwise  it  will  reflect  the  new
              directory.

       zftp_progress
              If  this function is set by the user, it will be called during a get, put or append
              operation each time sufficient data has been received from the host.  During a get,
              the data is sent to standard output, so it is vital that this function should write
              to standard error or directly to the terminal, not to standard output.

              When it is called with a transfer  in  progress,  the  following  additional  shell
              parameters are set:

              ZFTP_FILE
                     The name of the remote file being transferred from or to.

              ZFTP_TRANSFER
                     A G for a get operation and a P for a put operation.

              ZFTP_SIZE
                     The total size of the complete file being transferred: the same as the first
                     value provided by the remote and local subcommands for  a  particular  file.
                     If the server cannot supply this value for a remote file being retrieved, it
                     will not be set.  If input is from a pipe the value  may  be  incorrect  and
                     correspond simply to a full pipe buffer.

              ZFTP_COUNT
                     The amount of data so far transferred; a number between zero and $ZFTP_SIZE,
                     if that is set.  This number is always available.

              The  function  is  initially  called  with  ZFTP_TRANSFER  set  appropriately   and
              ZFTP_COUNT  set  to  zero.   After  the  transfer is finished, the function will be
              called one more time with ZFTP_TRANSFER set to GF or PF, in case it wishes to  tidy
              up.  It is otherwise never called twice with the same value of ZFTP_COUNT.

              Sometimes  the progress meter may cause disruption.  It is up to the user to decide
              whether the function should be defined and to use unfunction when necessary.

   Problems
       A connection may not be opened in the left hand side  of  a  pipe  as  this  occurs  in  a
       subshell  and  the file information is not updated in the main shell.  In the case of type
       or mode changes or closing the connection in a subshell, the information is  returned  but
       variables  are not updated until the next call to zftp.  Other status changes in subshells
       will not be reflected by changes to the variables (but should be otherwise harmless).

       Deleting sessions while a zftp command is active in the  background  can  have  unexpected
       effects,  even  if  it  does not use the session being deleted.  This is because all shell
       subprocesses share information on the state of all connections,  and  deleting  a  session
       changes the ordering of that information.

       On  some  operating  systems,  the control connection is not valid after a fork(), so that
       operations in subshells, on the left hand side of a pipeline, or in the background are not
       possible, as they should be.  This is presumably a bug in the operating system.

THE ZSH/ZLE MODULE

       The zsh/zle module contains the Zsh Line Editor.  See zshzle(1).

THE ZSH/ZLEPARAMETER MODULE

       The  zsh/zleparameter  module  defines  two  special parameters that can be used to access
       internal information of the Zsh Line Editor (see zshzle(1)).

       keymaps
              This array contains the names of the keymaps currently defined.

       widgets
              This associative array contains one entry per widget. The name of the widget is the
              key and the value gives information about the widget. It is either
                the string `builtin' for builtin widgets,
                a string of the form `user:name' for user-defined widgets,
                  where name is the name of the shell function implementing the widget,
                a string of the form `completion:type:name'
                  for completion widgets,
                or a null value if the widget is not yet fully defined.  In the penultimate case,
              type is the name of the builtin  widget  the  completion  widget  imitates  in  its
              behavior  and  name  is  the name of the shell function implementing the completion
              widget.

THE ZSH/ZPROF MODULE

       When loaded, the zsh/zprof causes shell functions to be profiled.  The  profiling  results
       can be obtained with the zprof builtin command made available by this module.  There is no
       way to turn profiling off other than unloading the module.

       zprof [ -c ]
              Without the -c option, zprof lists  profiling  results  to  standard  output.   The
              format is comparable to that of commands like gprof.

              At the top there is a summary listing all functions that were called at least once.
              This summary is sorted in decreasing order of the amount of  time  spent  in  each.
              The lines contain the number of the function in order, which is used in other parts
              of the list in suffixes of the form `[num]', then the number of calls made  to  the
              function.   The  next  three  columns  list  the  time in milliseconds spent in the
              function and its descendants,  the  average  time  in  milliseconds  spent  in  the
              function and its descendants per call and the percentage of time spent in all shell
              functions used in this function and its descendants.  The following  three  columns
              give the same information, but counting only the time spent in the function itself.
              The final column shows the name of the function.

              After the summary, detailed information about every function that  was  invoked  is
              listed, sorted in decreasing order of the amount of time spent in each function and
              its descendants.  Each of these entries consists of descriptions for the  functions
              that  called  the  function  described, the function itself, and the functions that
              were called from it.  The description for the function itself has the  same  format
              as in the summary (and shows the same information).  The other lines don't show the
              number of the function at the beginning and have their function named  indented  to
              make  it  easier  to  distinguish  the  line  showing the function described in the
              section from the surrounding lines.

              The information shown in this case is almost the same as in the summary,  but  only
              refers  to the call hierarchy being displayed.  For example, for a calling function
              the column showing the total running time lists the time  spent  in  the  described
              function  and  its  descendants  only  for  the  times when it was called from that
              particular calling function.  Likewise, for a called function, this  columns  lists
              the  total time spent in the called function and its descendants only for the times
              when it was called from the function described.

              Also in this case, the column showing the number of calls to a function also  shows
              a slash and then the total number of invocations made to the called function.

              As  long  as  the  zsh/zprof  module is loaded, profiling will be done and multiple
              invocations of the zprof builtin command will show the times and numbers  of  calls
              since  the  module  was loaded.  With the -c option, the zprof builtin command will
              reset its internal counters and will not show the listing.

THE ZSH/ZPTY MODULE

       The zsh/zpty module offers one builtin:

       zpty [ -e ] [ -b ] name [ arg ... ]
              The arguments following name are concatenated with spaces between, then executed as
              a  command,  as  if  passed  to  the  eval builtin.  The command runs under a newly
              assigned pseudo-terminal; this is useful  for  running  commands  non-interactively
              which  expect an interactive environment.  The name is not part of the command, but
              is used to refer to this command in later calls to zpty.

              With the -e option, the pseudo-terminal is set up  so  that  input  characters  are
              echoed.

              With  the  -b  option,  input  to  and  output  from  the  pseudo-terminal are made
              non-blocking.

              The shell parameter REPLY is set to the file descriptor assigned to the master side
              of  the  pseudo-terminal.   This  allows  the  terminal  to  be  monitored with ZLE
              descriptor handlers (see zshzle(1)) or manipulated with sysread and  syswrite  (see
              THE  ZSH/SYSTEM  MODULE in zshmodules(1)).  Warning: Use of sysread and syswrite is
              not recommended; use zpty -r and zpty -w unless  you  know  exactly  what  you  are
              doing.

       zpty -d [ name ... ]
              The second form, with the -d option, is used to delete commands previously started,
              by supplying a list of their names.  If no name is given, all commands are deleted.
              Deleting a command causes the HUP signal to be sent to the corresponding process.

       zpty -w [ -n ] name [ string ... ]
              The  -w  option  can be used to send the to command name the given strings as input
              (separated by spaces).  If the -n option is not given, a newline is  added  at  the
              end.

              If no string is provided, the standard input is copied to the pseudo-terminal; this
              may stop before copying the full input if the pseudo-terminal is non-blocking.  The
              exact input is always copied: the -n option is not applied.

              Note  that  the  command  under  the  pseudo-terminal sees this input as if it were
              typed, so beware when sending special tty driver  characters  such  as  word-erase,
              line-kill, and end-of-file.

       zpty -r [ -mt ] name [ param [ pattern ] ]
              The -r option can be used to read the output of the command name.  With only a name
              argument,  the  output  read  is  copied  to  the  standard  output.   Unless   the
              pseudo-terminal  is  non-blocking,  copying  continues  until the command under the
              pseudo-terminal exits; when non-blocking, only as much  output  as  is  immediately
              available is copied.  The return status is zero if any output is copied.

              When  also  given  a  param  argument,  at  most one line is read and stored in the
              parameter named param.  Less than a full line may be read if the pseudo-terminal is
              non-blocking.   The  return  status  is zero if at least one character is stored in
              param.

              If a pattern is given as well, output is read until the whole string  read  matches
              the  pattern,  even  in  the  non-blocking  case.  The return status is zero if the
              string read matches the pattern, or if the command has  exited  but  at  least  one
              character  could  still be read.  If the option -m is present, the return status is
              zero only if the pattern matches.  As of this writing, a maximum of one megabyte of
              output  can  be  consumed this way; if a full megabyte is read without matching the
              pattern, the return status is non-zero.

              In all cases, the return status is non-zero if nothing could be read, and is  2  if
              this is because the command has finished.

              If  the  -r  option  is  combined  with the -t option, zpty tests whether output is
              available before trying to read.  If  no  output  is  available,  zpty  immediately
              returns  the status 1.  When used with a pattern, the behaviour on a failed poll is
              similar to when the command has exited:  the return value is zero if at  least  one
              character could still be read even if the pattern failed to match.

       zpty -t name
              The -t option without the -r option can be used to test whether the command name is
              still running.  It returns a zero status if the command is running and  a  non-zero
              value otherwise.

       zpty [ -L ]
              The  last  form,  without  any  arguments,  is  used to list the commands currently
              defined.  If the -L option is given, this is done in the form of calls to the  zpty
              builtin.

THE ZSH/ZSELECT MODULE

       The zsh/zselect module makes available one builtin command:

       zselect [ -rwe ] [ -t timeout ] [ -a array ] [ -A assoc ] [ fd ... ]
              The  zselect builtin is a front-end to the `select' system call, which blocks until
              a file descriptor is ready for reading or writing, or has an error condition,  with
              an  optional  timeout.  If this is not available on your system, the command prints
              an error message and returns status 2 (normal errors return status  1).   For  more
              information,  see  your  systems  documentation  for  select(3).   Note there is no
              connection with the shell builtin of the same name.

              Arguments and options may be intermingled in any order.  Non-option  arguments  are
              file descriptors, which must be decimal integers.  By default, file descriptors are
              to be tested for reading, i.e. zselect will return when data  is  available  to  be
              read  from  the  file descriptor, or more precisely, when a read operation from the
              file descriptor will not block.  After a -r, -w and -e, the given file  descriptors
              are  to  be tested for reading, writing, or error conditions.  These options and an
              arbitrary list of file descriptors may be given in any order.

              (The presence of an `error condition' is not well defined in the documentation  for
              many  implementations  of  the select system call.  According to recent versions of
              the POSIX specification, it is really an exception condition,  of  which  the  only
              standard  example  is  out-of-band  data  received  on  a socket.  So zsh users are
              unlikely to find the -e option useful.)

              The option `-t timeout' specifies a timeout in hundredths of a second.  This may be
              zero,  in  which  case  the file descriptors will simply be polled and zselect will
              return immediately.  It is possible to call zselect with no file descriptors and  a
              non-zero timeout for use as a finer-grained replacement for `sleep'; note, however,
              the return status is always 1 for a timeout.

              The option `-a array' indicates that array should  be  set  to  indicate  the  file
              descriptor(s) which are ready.  If the option is not given, the array reply will be
              used for this purpose.  The array will contain a string similar  to  the  arguments
              for zselect.  For example,

                     zselect -t 0 -r 0 -w 1

              might  return  immediately  with status 0 and $reply containing `-r 0 -w 1' to show
              that both file descriptors are ready for the requested operations.

              The option `-A assoc' indicates that the associative array assoc should be  set  to
              indicate  the file descriptor(s) which are ready.  This option overrides the option
              -a, nor will reply be modified.  The keys of assoc are the  file  descriptors,  and
              the corresponding values are any of the characters `rwe' to indicate the condition.

              The  command  returns  status 0 if some file descriptors are ready for reading.  If
              the operation timed out, or a timeout of 0 was given and no file  descriptors  were
              ready,  or  there  was  an error, it returns status 1 and the array will not be set
              (nor modified in any way).  If there was an  error  in  the  select  operation  the
              appropriate error message is printed.

THE ZSH/ZUTIL MODULE

       The zsh/zutil module only adds some builtins:

       zstyle [ -L [ metapattern [ style ] ] ]
       zstyle [ -e | - | -- ] pattern style string ...
       zstyle -d [ pattern [ style ... ] ]
       zstyle -g name [ pattern [ style ] ]
       zstyle -{a|b|s} context style name [ sep ]
       zstyle -{T|t} context style [ string ... ]
       zstyle -m context style pattern
              This  builtin  command  is  used  to define and lookup styles.  Styles are pairs of
              names and values, where the values consist of any  number  of  strings.   They  are
              stored  together  with  patterns  and lookup is done by giving a string, called the
              `context', which is matched against the patterns.  The definition  stored  for  the
              most specific pattern that matches will be returned.

              A  pattern  is  considered  to  be  more  specific than another if it contains more
              components (substrings separated by colons) or if the patterns for  the  components
              are  more  specific,  where  simple strings are considered to be more specific than
              patterns and complex patterns are considered to be more specific than  the  pattern
              `*'.   A  `*'  in  the  pattern  will match zero or more characters in the context;
              colons are not treated specially in this  regard.   If  two  patterns  are  equally
              specific, the tie is broken in favour of the pattern that was defined first.

              Example

              For example, to define your preferred form of precipitation depending on which city
              you're in, you might set the following in your zshrc:

                     zstyle ':weather:europe:*' preferred-precipitation rain
                     zstyle ':weather:europe:germany:* preferred-precipitation none
                     zstyle ':weather:europe:germany:*:munich' preferred-precipitation snow

              Then, the fictional `weather' plugin might run under the hood a command such as

                     zstyle -s ":weather:${continent}:${country}:${county}:${city}" preferred-precipitation REPLY

              in order to retrieve your preference into the scalar variable $REPLY.

              Usage

              The forms that operate on patterns are the following.

              zstyle [ -L [ metapattern [ style ] ] ]
                     Without arguments, lists style definitions.  Styles are shown in  alphabetic
                     order and patterns are shown in the order zstyle will test them.

                     If  the  -L option is given, listing is done in the form of calls to zstyle.
                     The optional first argument, metapattern, is a pattern which will be matched
                     against  the  string  supplied as pattern when the style was defined.  Note:
                     this means, for example, `zstyle -L ":completion:*"' will match any supplied
                     pattern   beginning   `:completion:',   not   just   ":completion:*":    use
                     ':completion:\*' to match that.  The optional  second  argument  limits  the
                     output  to  a specific style (not a pattern).  -L is not compatible with any
                     other options.

              zstyle [ - | -- | -e ] pattern style string ...
                     Defines the given style for the pattern with the strings as the  value.   If
                     the  -e  option  is  given,  the  strings will be concatenated (separated by
                     spaces) and the resulting string will be evaluated (in the same way as it is
                     done by the eval builtin command) when the style is looked up.  In this case
                     the parameter `reply' must be assigned to set the strings returned after the
                     evaluation.  Before evaluating the value, reply is unset, and if it is still
                     unset after the evaluation, the style is treated as if it were not set.

              zstyle -d [ pattern [ style ... ] ]
                     Delete style definitions. Without arguments  all  definitions  are  deleted,
                     with  a  pattern  all  definitions  for  that pattern are deleted and if any
                     styles are given, then only those styles are deleted for the pattern.

              zstyle -g name [ pattern [ style ] ]
                     Retrieve a style definition. The name is used as the name  of  an  array  in
                     which  the  results  are stored. Without any further arguments, all patterns
                     defined are returned. With a pattern the styles defined for that pattern are
                     returned  and  with  both  a  pattern and a style, the value strings of that
                     combination is returned.

              The other forms can be used to look up or test styles for a given context.

              zstyle -s context style name [ sep ]
                     The parameter name is set to the value of the style interpreted as a string.
                     If  the value contains several strings they are concatenated with spaces (or
                     with the sep string if that is given) between them.

                     Return 0 if the style is set, 1 otherwise.

              zstyle -b context style name
                     The value is stored in name as a boolean, i.e. as the string  `yes'  if  the
                     value  has only one string and that string is equal to one of `yes', `true',
                     `on', or `1'. If the value is any other string or has more than one  string,
                     the parameter is set to `no'.

                     Return 0 if name is set to `yes', 1 otherwise.

              zstyle -a context style name
                     The  value  is  stored  in  name  as  an  array.  If  name is declared as an
                     associative array,  the first, third, etc. strings are used as the keys  and
                     the other strings are used as the values.

                     Return 0 if the style is set, 1 otherwise.

              zstyle -t context style [ string ... ]
              zstyle -T context style [ string ... ]
                     Test  the  value  of a style, i.e. the -t option only returns a status (sets
                     $?).  Without any string the return status is zero if the style  is  defined
                     for  at  least  one  matching pattern, has only one string in its value, and
                     that is equal to one of `true', `yes', `on' or `1'. If any strings are given
                     the status is zero if and only if at least one of the strings is equal to at
                     least one of the strings in the value. If the style is defined  but  doesn't
                     match, the return status is 1. If the style is not defined, the status is 2.

                     The  -T  option tests the values of the style like -t, but it returns status
                     zero (rather than 2) if the style is not defined for any matching pattern.

              zstyle -m context style pattern
                     Match a value. Returns status zero if the pattern matches at  least  one  of
                     the strings in the value.

       zformat -f param format spec ...
       zformat -a array sep spec ...
              This builtin provides two different forms of formatting. The first form is selected
              with the -f option. In this case the format string will be  modified  by  replacing
              sequences  starting  with  a  percent sign in it with strings from the specs.  Each
              spec should be of the form `char:string' which will cause every appearance  of  the
              sequence `%char' in format to be replaced by the string.  The `%' sequence may also
              contain optional minimum and maximum field width specifications between the `%' and
              the `char' in the form `%min.maxc', i.e. the minimum field width is given first and
              if the maximum field width is used, it has to be preceded by a dot.   Specifying  a
              minimum  field  width  makes  the  result be padded with spaces to the right if the
              string is shorter than the requested width.  Padding to the left can be achieved by
              giving  a negative minimum field width.  If a maximum field width is specified, the
              string will be truncated after that many characters.  After all `%'  sequences  for
              the  given  specs  have  been  processed,  the  resulting  string  is stored in the
              parameter param.

              The %-escapes also understand ternary expressions in the form used by prompts.  The
              % is followed by a `(' and then an ordinary format specifier character as described
              above.  There may be a set of digits either before or after the `('; these  specify
              a  test  number,  which  defaults  to zero.  Negative numbers are also allowed.  An
              arbitrary delimiter character follows the format specifier, which is followed by  a
              piece of `true' text, the delimiter character again, a piece of `false' text, and a
              closing parenthesis.  The complete expression (without the digits) thus looks  like
              `%(X.text1.text2)',  except  that  the `.' character is arbitrary.  The value given
              for the  format  specifier  in  the  char:string  expressions  is  evaluated  as  a
              mathematical  expression, and compared with the test number.  If they are the same,
              text1 is output, else text2 is output.  A parenthesis may be escaped  in  text2  as
              %).  Either of text1 or text2 may contain nested %-escapes.

              For example:

                     zformat -f REPLY "The answer is '%3(c.yes.no)'." c:3

              outputs  "The answer is 'yes'." to REPLY since the value for the format specifier c
              is 3, agreeing with the digit argument to the ternary expression.

              The second form, using the -a option, can be used for aligning strings.  Here,  the
              specs  are of the form `left:right' where `left' and `right' are arbitrary strings.
              These strings are modified by replacing the colons by the sep  string  and  padding
              the  left  strings  with  spaces to the right so that the sep strings in the result
              (and hence the right strings after them) are all aligned if the strings are printed
              below  each  other.  All strings without a colon are left unchanged and all strings
              with an empty right string have the trailing colon  removed.   In  both  cases  the
              lengths  of  the  strings are not used to determine how the other strings are to be
              aligned.  A colon in the  left  string  can  be  escaped  with  a  backslash.   The
              resulting strings are stored in the array.

       zregexparse
              This implements some internals of the _regex_arguments function.

       zparseopts [ -D -E -F -K -M ] [ -a array ] [ -A assoc ] [ - ] spec ...
              This  builtin  simplifies the parsing of options in positional parameters, i.e. the
              set of arguments given by $*.  Each spec describes one option and must  be  of  the
              form  `opt[=array]'.   If  an  option  described  by opt is found in the positional
              parameters it is copied into the  array  specified  with  the  -a  option;  if  the
              optional  `=array'  is given, it is instead copied into that array, which should be
              declared as a normal array and never as an associative array.

              Note that it is an error to give any spec without an `=array' unless one of the  -a
              or -A options is used.

              Unless  the  -E  option  is  given,  parsing  stops  at the first string that isn't
              described by one of the specs.  Even with -E, parsing always stops at a  positional
              parameter equal to `-' or `--'. See also -F.

              The  opt  description  must be one of the following.  Any of the special characters
              can appear in the option name provided it is preceded by a backslash.

              name
              name+  The name is the name of the option without the leading `-'.   To  specify  a
                     GNU-style  long option, one of the usual two leading `-' must be included in
                     name; for example, a `--file' option is represented by a name of `-file'.

                     If a `+' appears after name, the option is appended to array each time it is
                     found in the positional parameters; without the `+' only the last occurrence
                     of the option is preserved.

                     If one of these forms is used, the option  takes  no  argument,  so  parsing
                     stops  if the next positional parameter does not also begin with `-' (unless
                     the -E option is used).

              name:
              name:-
              name:: If one or two colons are given, the  option  takes  an  argument;  with  one
                     colon,  the  argument  is mandatory and with two colons it is optional.  The
                     argument is appended to the array after the option itself.

                     An optional argument is put into the same array element as the  option  name
                     (note  that  this  makes  empty  strings as arguments indistinguishable).  A
                     mandatory argument is added as a separate element unless the  `:-'  form  is
                     used, in which case the argument is put into the same element.

                     A `+' as described above may appear between the name and the first colon.

              In  all cases, option-arguments must appear either immediately following the option
              in the same positional parameter or in the next one. Even an optional argument  may
              appear  in  the  next  parameter, unless it begins with a `-'.  There is no special
              handling of `=' as with GNU-style argument parsers; given  the  spec  `-foo:',  the
              positional parameter `--foo=bar' is parsed as `--foo' with an argument of `=bar'.

              When the names of two options that take no arguments overlap, the longest one wins,
              so that parsing for the specs `-foo -foobar' (for example) is unambiguous. However,
              due  to the aforementioned handling of option-arguments, ambiguities may arise when
              at least one overlapping spec takes an argument, as in  `-foo:  -foobar'.  In  that
              case, the last matching spec wins.

              The  options of zparseopts itself cannot be stacked because, for example, the stack
              `-DEK' is indistinguishable from a spec for the GNU-style long option `--DEK'.  The
              options of zparseopts itself are:

              -a array
                     As  described  above,  this  names  the  default array in which to store the
                     recognised options.

              -A assoc
                     If this is given, the  options  and  their  values  are  also  put  into  an
                     associative  array  with the option names as keys and the arguments (if any)
                     as the values.

              -D     If this option is given, all options found are removed from  the  positional
                     parameters  of  the calling shell or shell function, up to but not including
                     any not described by the specs.  If the first such parameter is `-' or `--',
                     it is removed as well.  This is similar to using the shift builtin.

              -E     This  changes  the  parsing rules to not stop at the first string that isn't
                     described by one of the specs.  It can be used  to  test  for  or  (if  used
                     together  with  -D)  extract options and their arguments, ignoring all other
                     options and  arguments  that  may  be  in  the  positional  parameters.   As
                     indicated  above, parsing still stops at the first `-' or `--' not described
                     by a spec, but it is not removed when used with -D.

              -F     If  this  option  is  given,  zparseopts  immediately  stops  at  the  first
                     option-like  parameter  not  described  by one of the specs, prints an error
                     message, and returns status 1.  Removal (-D) and  extraction  (-E)  are  not
                     performed,   and  option  arrays  are  not  updated.   This  provides  basic
                     validation for the given options.

                     Note that the appearance in the positional parameters of an  option  without
                     its  required  argument  always  aborts  parsing  and  returns  an  error as
                     described above regardless of whether this option is used.

              -K     With this option, the arrays specified with  the  -a  option  and  with  the
                     `=array'  forms  are kept unchanged when none of the specs for them is used.
                     Otherwise the entire array is replaced  when  any  of  the  specs  is  used.
                     Individual  elements  of associative arrays specified with the -A option are
                     preserved by -K.  This allows assignment of default values to arrays  before
                     calling zparseopts.

              -M     This changes the assignment rules to implement a map among equivalent option
                     names.  If any spec uses the `=array' form, the string array is  interpreted
                     as  the  name  of  another  spec, which is used to choose where to store the
                     values.  If no other spec is found, the values are stored  as  usual.   This
                     changes  only  the  way  the values are stored, not the way $* is parsed, so
                     results  may  be  unpredictable   if   the   `name+'   specifier   is   used
                     inconsistently.

              For example,

                     set -- -a -bx -c y -cz baz -cend
                     zparseopts a=foo b:=bar c+:=bar

              will have the effect of

                     foo=(-a)
                     bar=(-b x -c y -c z)

              The arguments from `baz' on will not be used.

              As an example for the -E option, consider:

                     set -- -a x -b y -c z arg1 arg2
                     zparseopts -E -D b:=bar

              will have the effect of

                     bar=(-b y)
                     set -- -a x -c z arg1 arg2

              I.e.,  the option -b and its arguments are taken from the positional parameters and
              put into the array bar.

              The -M option can be used like this:

                     set -- -a -bx -c y -cz baz -cend
                     zparseopts -A bar -M a=foo b+: c:=b

              to have the effect of

                     foo=(-a)
                     bar=(-a '' -b xyz)