Usenet 1993 July/InfoMagic USENET CD-ROM July 1993.ISO/answers/unix-faq/shell/zsh

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From: [e-mail] (Peter Stephenson)
Newsgroups: comp.unix.shell,comp.answers,news.answers
Subject: Z-shell Frequently-Asked Questions
Summary: Q's and A's about zsh, a powerful (and free) UNIX shell
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Date: 23 Jun 93 16:13:04 GMT
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Archive-Name: unix-faq/shell/zsh
Last-Modified: 1993/06/23
Submitted-By: [e-mail] (Peter Stephenson)
Version: $Id: zsh.FAQ,v 1.11 1993/06/22 13:46:18 pws Exp pws $
Frequency: Monthly

This document contains a list of frequently-asked (or otherwise
significant) questions concerning the Z-shell, a command interpreter for
many UNIX systems which is freely available to anyone with FTP access.
Zsh is more powerful than every other common shell (sh, ksh, csh, tcsh
and bash) put together.

If you have never heard of `sh', `csh' or `ksh', then you are probably
better off to start by reading a general introduction to UNIX rather
than this document.

Another useful source of information is the collection of FAQ articles
posted frequently to the Usenet news groups comp.unix.questions,
comp.unix.shells and comp.answers with answers to general questions
about UNIX.  The fifth of the seven articles deals with shells,
including zsh, with a brief description of differences.  (This article
also talks about shell startup files which would otherwise rate a
mention here.)

If you just want to know how to get your hands on the latest version,
skip to question 4; if you want to know what to do with insoluble
problems, go to 20.

To encourage you to read on, if you don't know about zsh but are
familiar with other UNIX shells, here are some things that zsh is
particularly good at.  No claim of exclusivity is made, especially as
shells copy one another, though in the areas of command line editing and
globbing zsh is well ahead of the competition.  I am not aware of a
major feature in any other freely-available shell which zsh does not
also have.
  Command line editing:
    programmable completion: incorporates the ability to use
      the full power of zsh globbing (compctl -g),
    multi-line commands editable as a single buffer (even files!),
    variable editing (vared),
    command buffer stack,
    print text straight into the buffer for immediate editing (print -z),
    execution of unbound commands,
    menu completion,
    variable, editing function and option name completion,
    inline expansion of variables, history commands.
  Globbing --- extremely powerful, including:
    recursive globbing (cf. find),
    file attribute qualifiers (size, type, etc. also cf. find),
    full alternation and negation of patterns.
  Handling of multiple redirections (simpler than tee).
  Large number of options for tailoring.
  Path expansion (=foo -> /usr/bin/foo).
  Adaptable messages for spelling, watch, time as well as prompt
    (now including conditional expressions).
  Named directories.
  Comprehensive integer arithmetic.
  Manipulation of arrays (including reverse subscripting).
  Spelling correction (which works).


Notation: Quotes `like this' are ordinary textual quotation
marks.  Other uses of quotation marks are input to the shell.

Contents:
1) What is it?
2) On what machines will it run?
3) What's the latest version?
4) Where do I get it?
5) How does zsh differ from sh, ksh, csh,...?
6) Why do my csh aliases not work?  (Plus other alias pitfalls.)
7) How do I get the meta key to work on my xterm?
8) Why does my terminal act funny in way x?
9) Why does `$var' where var="foo bar" not do what I expect?
10) My PATH, (MANPATH, ...) sometimes doesn't handle tildes.  What gives?
11) How does base arithmetic work?
12) How do I get a newline in my prompt?
13) Why does `bindkey ^a command-name' or 'stty intr ^-' do something funny?
14) How do I execute command `foo' within function `foo'?
15) Why can't I get zsh to work with SGI's `userenv'?
16) Why do history substitutions with single bangs do something funny?
17) Why does zsh kill off all my background jobs when I logout?
18) I don't have root access: how do I make zsh my login shell?
19) What bugs are currently known and unfixed?
20) Where do I report bugs, get more info / who's working on zsh?
21) What's on the wish-list?
--- End of Contents ---


1) What is it?

  Zsh is a UNIX command interpreter (shell) which of the standard shells
  most resembles the Korn shell (ksh), although it is not completely
  compatible.  It includes enhancements of many types, notably in the
  command-line editor, options for customising its behaviour, filename
  globbing, features to make C-shell (csh) users feel more at home and
  extra features drawn from tcsh (another `custom' shell).

  It was written by Paul Falstad <[e-mail]> when a student at
  Princeton; however, Paul doesn't maintain it any more and enquiries
  should be sent to the mailing list (see question 20).  It is freely
  available to anyone under unrestrictive conditions.

  For more information, the files doc/intro.txt or doc/intro.troff
  included with the source distribution are highly recommended.  A list
  of features is given in FEATURES, also with the source.


2) On what machines will it run?

  Zsh was written for machines of the Berkeley UNIX family; most such
  machines (and all the most popular) will run it without major surgery.
  Modifications have been made so that it should work under SYSVR4-based
  operating systems such as Solaris 2.x and OSF/1.  This best thing is
  to suck it and see.  You may not have to change too much: if you do
  change anything, arrange for the shell script `buildzsh' to set the
  necessary #define's, etc., without human intervention.  Recent
  additions include Convex, Unicos and Linux support; there is a project
  to allow POSIX.1 compilation (but note that that zsh is not itself
  particularly POSIX-compliant at the moment).


3) What's the latest version?

  The latest production version is 2.3.1.  The current beta version is
  2.4.  New patches occur frequently and are added to the archive (next
  question).  At the time of writing the latest patch level was 164.

  The next production version will be 2.5 (2.4 will not be released, so
  as to minimise confusion over version numbers).  It is expected that
  no new features will be added before the release.


4) Where do I get it?

  Bas de Bakker ([e-mail]) is in charge of the archive and the
  latest version is available for users east of the Atlantic from:
    carlo.phys.uva.nl (145.18.220.25):/pub/bas/zsh/zsh-2.4beta.tar.gz
  The latest full release is in zsh-2.3.1.tar.gz in the same directory.
  Note that this is in gzip format: you will need GNU gzip (of which there
  is now a production version) from your nearest GNU archive to unpack it.
  There is also a version under RCS control which may be more suitable
  for source hackers.

  Rick Ohnemus has a reflector site in the USA:
        ftp.sterling.com (192.124.9.1):/zsh

  The 2.3.1 distribution is also available from ftp.uu.net and mirrors
  in the directory pub/shells/zsh.


5) How does zsh differ from sh, ksh, csh,...?

  As has already been mentioned, zsh is most similar to ksh, while many
  of the additions are to please csh users.

  i) ksh:
  Most features of ksh (and hence also of sh) are implemented in zsh;
  problems can arise because the implementation is slightly different.
  Note also that not all ksh's are the same either.  I have based this
  on SunOS 4, which is essentially the 11/16/88 version of ksh.

  Various options can be turned on which will increase ksh
  compatibility, though decrease zsh's abilities: see the manual entries
  for IGNORE_BRACES (though brace expansion occurs in some versions of
  ksh), KSH_OPTION_PRINT, NO_BANG_HIST, NO_EQUALS, NO_HUP, NO_RCS,
  NO_SHORT_LOOPS, PROMPT_SUBST, RM_STAR_SILENT, SH_WORD_SPLIT (see
  question 14) and SINGLE_LINE_ZLE.  Note that you can also disable any
  built-in commands which get in your way.  If invoked as `ksh', the
  shell will try and set suitable options.

  Differences from ksh which might prove significant for ksh
  programmers, some of which may be interpreted as bugs (there must be
  more) include:
  Syntax:
    Shell word splitting: see question 14.  (This is particularly
      frequently asked about.)
    Arrays are more csh-like than ksh-like:
      subscripts start at 1, not 0; array[0] refers to array[1];
      `$array' refers to the whole array, not $array[0];
      braces are unnecessary: $a[1] == ${a[1]}, etc.
    Coprocesses are established by `coproc'; `|&' behaves like csh.
  Command line substitutions, globbing etc.:
    The $((...)) version of numeric evaluation is not implemented; use $[...].
    Treatment of backslashes within backquotes is different.
    PS1 does not do parameter substitution by default (promptsubst option).
    Globbing does not allow ksh-style `pattern-lists'.
    Unquoted assignments do file expansion after ':'s (intended for PATHs).
  Command execution:
    The PATH is not searched for commands specified at invocation without -c.
    There is no ENV variable (use /etc/zshrc, ~/.zshrc; note also ZDOTDIR).
  Aliases and functions:
    Functions will call themselves recursively: see question 14.
    The order in which aliases and functions are defined is significant
      (function definitions with () expand aliases -- see question 6).
    Aliases and functions cannot be exported.
    There are no tracked aliases: command hashing replaces these.
    The use of aliases for key bindings is replaced by `bindkey'.
    Traps are not local to functions and are not reset automatically
      when called.
  Editing:
    The options emacs, gmacs, privileged, trackall, viraw are not supported.
      (Use bindkey to change the editing behaviour.)
    The `keyword' option does not exist and -k is instead interactivecomments.
    Management of histories in multiple shells is different:
      the history list is not saved and restored after each command.
    \ does not escape editing chars (use ^V).
    Not all ksh bindings are set (e.g. `<ESC>#').
  Built-in commands:
    No built-in commands cause automatic termination of a script on
     failure (e.g., `. file' in a script doesn't cause it to bail out
     if `file' doesn't exist).
    Some built-ins (true, false, r, ...) were aliases in ksh.
    [ ] is a shell built-in, rather than a call to /bin/test.
      (but you can disable the built-in).  It is also a bit
      over-enthusiastic about recognising -o's and -a's.
    There is no built-in command newgrp: use a shell function.
    `jobs' has no `-n' flag.
    In `let "i = foo"', foo is evaluated as a number, not an expression
      (although in `let "i = $foo"' it is treated as an expression).
  Other idiosyncracies:
    `select' always redisplays the list of selections on each loop.

  ii) csh:

  Although certain features aim to ease the withdrawal symptoms of csh
  (ab)users, the syntax is in general rather different and you should
  certainly not try to run scripts without modification.  The c2z script
  is provided with the source (in scripts/c2z) to help convert .cshrc
  and .login files; see also the next question concerning aliases,
  particularly those with arguments.

  Csh-compatibility additions include:
    Logout, rehash, source, (un)limit built-in commands.
    *rc file for interactive shells.
    Directory stacks.
    Cshjunkie*, ignoreeof options.
    The nonomatch option.
    >&, |& etc. redirection.
    foreach ... loops; alternate syntax for other loops.
    $PROMPT as well as $PS1, $status as well as $?, $#argv as well as $#, ....
    Escape sequences via % for prompts.
    Special array variables $PATH etc. are colon-separated, $path are arrays.
    !-type history (which may be turned off via `setopt nobanghist').
    Arrays have csh-like features (see i)).

  iii) tcsh:

  Certain features have been borrowed from tcsh, including $watch,
  run-help, $savehist, $histlit, periodic commands etc., extended
  prompts, sched and which/where built-ins.  Programmable completion was
  inspired by, but is entirely different to, tcsh's `complete'. (There
  is a perl script called lete2ctl in the scripts directory of the
  source distribution to convert `complete' to `compctl' statements.)
  This list is not definitive: some features have gone in the other
  direction.

  If you're missing the editor function run-fg-editor, try something
  with bindkey -s (which binds a string to a keystroke), e.g.
    bindkey -s '^z' '\eqfg %$EDITOR:t\n'
  which pushes the current line onto the stack and tries to bring a job
  with the basename of your editor into the foreground.  With a bit
  of playing around you can implement run-fg-anything.


6) Why do my csh aliases not work?  (Plus other alias pitfalls.)

  First of all, check you are using the syntax
    alias newcmd='list of commands'
  and not
    alias newcmd 'list of commands'
  which won't work. (It tells you if `newcmd' and `list of commands' are
  already defined as aliases.)

  Otherwise, your aliases probably contain references to the command
  line of the form `\!*', etc.  Zsh does not handle this behaviour as it
  has shell functions which provide a way of solving this problem more
  consistent with other forms of argument handling.  For example, the
  csh alias
    alias cd 'cd \!*; echo $cwd'
  can be replaced by the zsh function,
    cd() { builtin cd $*; echo $PWD; }
  (the `builtin' tells zsh to use its own `cd', avoiding an infinite loop)
  or, perhaps better,
    cd() { builtin cd $*; print -D $PWD; }
  (which converts your home directory to a ~).  In fact, this problem is
  better solved by defining the special function chpwd() (see the manual).
  Note also that the `;' at the end of the function is optional in zsh,
  but not in ksh or sh (for sh's where it exists).

  Here is Bart Schaefer's guide to converting csh aliases for zsh.

    1.  If the csh alias references "parameters" (\!:1 \!* etc.),
        then in zsh you need a function (referencing $1 $* etc.).
        Otherwise, you can use a zsh alias.

    2.  If you use a zsh function, you need to refer _at_least_ to
        $* in the body (inside the { }).  Parameters don't magically
        appear inside the { } the way they get appended to an alias.

    3.  If the csh alias references its own name (alias rm "rm -i"),
        then in a zsh function you need the "command" keyword
        (function rm() { command rm -i $* }), but in a zsh alias
        you don't (alias rm="rm -i").

    4.  If you have aliases that refer to each other (alias ls "ls -C";
        alias lf "ls -F" ==> lf == ls -C -F) then you must either:
        a.  convert all of them to zsh functions; or
        b.  after converting, be sure your .zshrc defines all of your
            aliases before it defines any of your functions.

    Those first four are all you really need, but here are four more for
    heavy csh alias junkies:

    5.  Mapping from csh alias "parameter referencing" into zsh function
        (assuming shwordsplit is NOT set in zsh):
             csh                   zsh
            =====               ==========
            \!*                 $*              (or $argv)
            \!^                 $1              (or $argv[1])
            \!:1                $1
            \!:2                $2              (or $argv[2], etc.)
            \!$                 $*[$#]          (or $argv[$#], or $*[-1])
            \!:1-4              $*[1,4]
            \!:1-               $*[1,$#-1]      (or $*[1,-2])
            \!^-                $*[1,$#-1]
            \!*:q               "$@"            ($*:q doesn't work (yet))
            \!*:x               $=*             ($*:x doesn't work (yet))

    6.  Remember that it is NOT a syntax error in a zsh function to
        refer to a position ($1, $2, etc.) greater than the number of
        parameters. (E.g., in a csh alias, a reference to \!:5 will
        cause an error if 4 or fewer arguments are given; in a zsh
    function, $5 is the empty string if there are 4 or fewer
    parameters.)

    7.  To begin a zsh alias with a - (dash, hyphen) character, use
        "alias --":
                 csh                            zsh
            ===============             ==================
            alias - "fg %-"             alias -- -="fg %-"

    8.  Stay away from "alias -g" in zsh until you REALLY know what
        you're doing.

  There is one other serious problem with aliases: consider
        alias l='/bin/ls -F'
        l() { /bin/ls -la $* | more }
  `l' in the function definition is in command position and is expanded
  as an alias, defining `/bin/ls' and `-F' as functions which call
  `/bin/ls', which gets a bit recursive.  This can be avoided if you use
  `function' to define a function, which doesn't expand aliases.  It is
  possible to argue for extra warnings somewhere in this mess.  If you
  define `function' as an alias you deserve what you get.


7) How do I get the meta key to work on my xterm?

  As stated in the manual, zsh needs to be told about the meta key by
  using `bindkey -me' or `bindkey -mv' in your .zshrc or on the command
  line.  You probably also need to tell the terminal driver to allow the
  `meta' bit of the character through; `stty pass8' is the usual
  incantation.  Sample .zshrc entry:
    [[ $TERM = "xterm" ]] && stty pass8 && bindkey -me
  or, on SYSVR4-ish systems without pass8,
    [[ $TERM = "xterm" ]] && stty -parenb -istrip cs8 && bindkey -me
  (disable parity detection, don't strip high bit, use 8-bit characters).
  Make sure this comes *before* any bindkey entries in your .zshrc which
  redefine keys normally defined in the emacs/vi keymap.


8) Why does my terminal act funny in way x?

  If you are using an OpenWindows cmdtool as your terminal, any
  escape sequences (such as those produced by cursor keys) will be
  swallowed up and never reach zsh.  Either use shelltool or avoid
  commands with escape sequences.  You can also disable scrolling from
  the cmdtool pane menu (which effectively turns it into a shelltool).
  If you still want scrolling, try using an xterm with the scrollbar
  activated.

  If that's not the problem, and you are using stty to change some tty
  settings, make sure you haven't asked zsh to freeze the tty settings:
  type
    ttyctl -u
  before any stty commands you use.

  If _that's_ not the problem, and you are having difficulties with
  external commands (not part of zsh), and you think some terminal
  setting is wrong (e.g. ^V is getting interpreted as `literal next
  character' when you don't want it to be), try
    ttyctl -u
    STTY='lnext "^-"' commandname
  (in this example), or just export STTY for all commands to see.  Note
  that zsh doesn't reset the terminal completely afterwards: just the
  modes it uses itself and a number of special processing characters
  (see the stty(1) manual page).


9) Why does `$var' where var="foo bar" not do what I expect?

  In most Bourne-shell derivatives, multi-word variables such as
    var="foo bar"
  are split into words when passed to a command or used in a `for foo in
  $var' loop.  By default, zsh does not have that behaviour: the
  variable remains intact.  (This is not a bug!  See below.)  An option
  (shwordsplit) exists to provide compatibility.

  For example, defining the function args to show the number of its
  arguments:
    args() { echo $#; }
  and with our definition of vble,
    args $vble
  produces the output `1'.  After
    setopt shwordsplit
  the same function produces the output `2', as with sh and ksh.

  Unless you need strict sh/ksh compatibility, you should ask yourself
  whether you really want this behaviour, as it can produce unexpected
  effects for variables with entirely innocuous embedded spaces.  The
  natural way to produce word-splitting behaviour in zsh is via arrays.
  For example,
    set -A array one two three twenty
  (or
        array=(one two three twenty)
  if you prefer), followed by
    args $array
  produces the output `4', regardless of the setting of shwordsplit.
  Arrays are also much more versatile than single strings.

  Note also the "$@" method of word splitting is always available in zsh
  functions and scripts (though strictly this does array splitting, not
  word splitting), also the substitution ${=foo} to toggle word
  splitting on variable `foo'.


10) My PATH, (MANPATH, ...) sometimes doesn't handle tildes.  What gives?

  The code has recently been overhauled, so take a look at the latest
  version of 2.4beta.  This guarantees that no ~user expansion (or
  =command expansion, which takes place at the same time) will happen if
  the tilde is quoted, and also rationalises PATH-type variables by
  expanding all unquoted assignments as if they are colon-separated
  lists (so you may need to add or subtract a few extra quotes, but the
  results are more predictable).  In addition typeset, etc., now should
  behave like ordinary assignments in this respect; previously tildes in
  typeset assignments were unquotable.


11) How does base arithmetic work?

  The syntax (e.g. using the `let' builtin is)
    let 'foo = [16]ff'
  or equivalently
    (( foo = [16]ff ))
  Then
    echo $foo
  gives the answer `255'.  It is possible to declare variables explicitly
  to be integers, via
    typeset -i foo
  which has a different effect: namely the base used in the first
  assignment (hexadecimal in the example) is subsequently used whenever
  `foo' is displayed (although the internal representation is unchanged).
  To ensure foo is always displayed in decimal, declare it as
    typeset -i 10 foo
  which requests base 10 for output.  You can change the output base of an
  existing variable in this fashion.  Using the `$[ ... ]' method will
  always display in decimal.


12) How do I get a newline in my prompt?

  You can place a literal newline in quotes, i.e.
    PROMPT="Hi Joe,
    what now?%# "
  If you have the bad taste to set the option cshjunkiequotes, which
  inhibits such behaviour, you will have to bracket this with
  `unsetopt cshjunkiequotes' and `setopt cshjunkiequotes', or put it in
  your .zshrc before the option is set.


13) Why does `bindkey ^a command-name' or 'stty intr ^-' do something funny?

  You probably have the extendedglob option set in which case ^ and #
  are metacharacters.  ^a matches any file except one called a, so the
  line is interpreted as bindkey followed by a list of files.  Quote the
  ^ with a backslash or put quotation marks around ^a.


14) How do I execute command `foo' within function `foo'?

  The command `command foo' does just that.  You don't need this with
  aliases, but you do with functions.  Note that error messages like
        zsh: job table full or recursion limit exceeded
  are a good sign that you tried calling `foo' in function `foo' without
  using `command'.  (In ksh, functions were never called recursively.)


15) I can't get zsh to work with SGI's `userenv'.

  It seems the Silicon Graphics `userenv' command interacts weirdly with
  the line editor (zsh is not unique in this respect).  Add this line to
  the top of your .zshenv file:
        if [[ "${ENVONLY:-0}" -eq 1 ]]; then unsetopt zle; fi
  --- which will turn the line editor off if it sees a `userenv' coming.
  Don't turn zle back on with setopt until [[ $ENVONLY -ne 1 ]].


16) Why do history substitutions with single bangs do something funny?

  If you have a command like "echo !-2:$ !$", the first history
  substitution then sets a default to which later history substitutions
  with single unqualified bangs refer, so that !$ becomes equivalent to
  !-2:$.  The option CSH_JUNKIE_HISTORY makes all single bangs refer
  to the last command.


17) Why does zsh kill off all my background jobs when I logout?

  Simple answer: you haven't asked it not to.  Zsh (unlike [t]csh) gives
  you the option of having background jobs killed or not: the `nohup'
  option exists if you don't want them killed.  Note that you can always
  run programs with `nohup' in front of the pipeline whether or not the
  option is set, which will prevent that job from being killed on
  logout.  (Nohup is actually an external command.)

  The `disown' builtin is very useful in this respect: if zsh informs
  you that you have background jobs when you try to logout, you can
  `disown' all the ones you don't want killed when you exit.  This is
  also a good way of making jobs you don't need the shell to know about
  (such as commands which create new windows) invisible to the shell.


18) I don't have root access: how do I make zsh my login shell?

  Unfortunately, on many machines you can't use `chsh' to change your
  shell unless the name of the shell is contained in /etc/shells, so if
  you have your own copy of zsh you need some sleight-of-hand to use it
  when you log on.  (Simply typing `zsh' is not really a solution since
  you still have your original login shell waiting for when you exit.)

  The basic idea is to use `exec <zsh-path>' to replace the current
  shell with zsh.  Often you can do this in a login file such as
  .profile (if your shell is sh or ksh) or .login (if it's csh).  Make
  sure you have some way of altering the file (e.g. via FTP) before you
  try this as `exec' is often rather unforgiving.

  In .profile, try something like
    [ -f $HOME/bin/zsh ] && exec $HOME/bin/zsh -l
  and in .login, try something like
    if ( -f ~/bin/zsh ) exec ~/bin/zsh -l
  (in each case the -l tells zsh it is a login shell).

  It's not a good idea to put this (even without the -l) into .cshrc, at
  least without some tests on what the csh is supposed to be doing, as
  that will cause _every_ instance of csh to turn into a zsh and will
  cause csh scripts (yes, unfortunately some people write these) which
  do not call `csh -f' to fail.  If you want to tell xterm to run zsh,
  change the SHELL environment variable to the full path of zsh at the
  same time as you exec zsh.  If you have to exec zsh from your .cshrc,
  a minimum safety check is `if ($?prompt) ...'.

  If you like your login shell to appear in the process list as '-zsh',
  you can link zsh to -zsh (e.g. by `ln -s ~/bin/zsh ~/bin/-zsh') and
  change the exec to `exec -zsh'.  (Make sure -zsh is in your path.)
  This has the same effect as the `-l' option.

  Footnote: if you DO have root access, make sure zsh goes in
  /etc/shells on all appropriate machines, including NIS clients, or you
  may have problems with FTP to that machine.


19) What bugs are currently known and unfixed?

  Here are some of the more well-known ones, very roughly in decreasing
  order of significance.  A fuller bug list is now maintained by Carlos
  Carvalho <[e-mail]>.  Many of these can also be counted
  against differences from ksh in question 5); note that this applies to
  the latest beta version and that simple bugs are often fixed quite
  quickly.

  (?? Weird command hashing problems e.g. with command completion,
    only experienced by some users ??)
  Lines which spill over the right margin cannot be cut/pasted properly
    (not necessarily a bug, but highly annoying).
  Pipelines ending in a while/until/for loop are uninterruptible.
  Certain built-ins won't allow the `VAR=value command ...' assignment;
    the ones that do don't unset VAR after use (may not really be a bug).
    (N.B.: `exec foo=bar command' is a workaround for exec.)
  The `histlit' option adds newlines to lines in the history
    (and is broken in several other ways, e.g. !:x word selection).
  `time' is ignored with builtins and can't be used with {...} or (...);
    in shells with no job control the command name is blank.
  $_ returns the last unexpanded word from the previous line (not command).
  The :q modifier doesn't split words and -q and -x don't work for variables.
  In vi mode, `u' can go past the original modification point.
  Autocd won't use globbed filenames.
  Linked directories can sometimes confuse zsh's idea of its cwd.
  Input processing of e.g. ^V is doing something weird in Solaris 2.
  Still problems under SCO Unix (a patch exists but hasn't been merged yet).

  Former bugs recently fixed (in archive now or soon):
    `return' in a shell script should have acted as `exit'.
    "$@" always indicated at least one argument.
    ${1+foo} always returned `foo' even if $1 was not set.
    Attempts to trap untrappable signals produced an incorrect message.
    Autoloaded functions with malformed [[...]] constructs dumped core.


20) Where do I report bugs, get more info / who's working on zsh?

  The shell is being maintained by various (entirely self-appointed)
  subscribers to the mailing list,
    [e-mail] so any suggestions, complaints,
  questions and matters for discussion should be sent there.  If you
  want someone to mail you directly, say so.  Most patches to zsh appear
  there first.

  A lower-volume list,
    [e-mail]
  exists for announcements of new features and proposed changes
  requiring some decisions.

  Both lists are handled by an automated server.  The instructions for
  zsh-announce are the same as for zsh-list: just change zsh-list to
  zsh-announce everywhere in the following.

  To join zsh-list, send email to
    [e-mail]
  containing
    subscribe zsh-list <optional-address>
  where <optional-address> can be blank if you want to subscribe from
  your current email address.  Send the message `help' to the same
  address for help on the list server; `unsubscribe zsh-list' also
  works. (Don't send this to the list!) The list manager, Rick Ohnemus,
  can be reached at
    [e-mail]
  (or `rick' at the same adress).

  The list (everything since May 1992) is archived in
    ftp.sterling.com:zsh/zsh-list/YY-MM
  where YY-MM are the year and month in digits.


21) What's on the wish-list?

  The shell is getting rather large and any simplifications would be
    appreciated.
  Option for glob qualifiers to follow perl syntax.
  Option to quote !-history lexically via '' but not ""..
  Binding of shell functions (or commands?) to key strokes --
    requires some way of accessing the editing buffer from functions
    and probably of executing zle functions as a command.
  Ksh/sh compatibility could be improved if required.
  The introduction to zsh (intro.*) could do with an update to reflect
    extended completion (in particular) and other recent additions.


Acknowledgments:

Thanks to zsh-list, in particular Bart Schaefer, for suggestions
regarding this document; thanks to Jim Mattson and more recently Bas de
Bakker for their hard work as archivists, and to Peter Gray for
maintaining the mailing list, without which zsh might easily have died,
and to the latest list maintainer, Rick Ohnemus.  The world is eternally
in the debt of Paul Falstad for inventing zsh in the first place.