User Commands ZSH(1)
NAME
zsh - the Z shell
OVERVIEW
Because zsh contains many features, the zsh manual has been
split into a number of sections:
zsh Zsh overview (this section)
zshmisc Anything not fitting into the other sections
zshexpn Zsh command and parameter expansion
zshparam Zsh parameters
zshoptions Zsh options
zshbuiltins Zsh built-in functions
zshzle Zsh command line editing
zshcompwid Zsh completion widgets
zshcompsys Zsh completion system
zshcompctl Zsh completion control
zshmodules Zsh loadable modules
zshzftpsys Zsh built-in FTP client
zshall Meta-man page containing all of the above
DESCRIPTION
Zsh is a UNIX command interpreter (shell) usable as an
interactive login shell and as a shell script command pro-
cessor. Of the standard shells, zsh most closely resembles
ksh but includes many enhancements. Zsh has command line
editing, builtin spelling correction, programmable command
completion, shell functions (with autoloading), a history
mechanism, and a host of other features.
AUTHOR
Zsh was originally written by Paul Falstad <pf@zsh.org>.
Zsh is now maintained by the members of the zsh-workers
mailing list <zsh-workers@sunsite.dk>. The development is
currently coordinated by Peter Stephenson <pws@zsh.org>.
The coordinator can be contacted at <coordinator@zsh.org>,
but matters relating to the code should generally go to the
mailing list.
AVAILABILITY
Zsh is available from the following anonymous FTP sites.
These mirror sites are kept frequently up to date. The
sites marked with (H) may be mirroring ftp.cs.elte.hu
instead of the primary site.
Primary site
ftp://ftp.zsh.org/pub/zsh/
http://www.zsh.org/pub/zsh/
Australia
ftp://ftp.zsh.org/pub/zsh/
http://www.zsh.org/pub/zsh/
Denmark
ftp://sunsite.dk/pub/unix/shells/zsh/
Finland
ftp://ftp.funet.fi/pub/unix/shells/zsh/
Germany
ftp://ftp.fu-berlin.de/pub/unix/shells/zsh/ (H)
ftp://ftp.gmd.de/packages/zsh/
ftp://ftp.uni-trier.de/pub/unix/shell/zsh/
Hungary
ftp://ftp.cs.elte.hu/pub/zsh/
http://www.cs.elte.hu/pub/zsh/
ftp://ftp.kfki.hu/pub/packages/zsh/
Israel
ftp://ftp.math.technion.ac.il/pub/zsh/
http://www.math.technion.ac.il/pub/zsh/
Japan
ftp://ftp.win.ne.jp/pub/shell/zsh/
ftp://ftp.ayamura.org/pub/zsh/
Korea
ftp://linux.sarang.net/mirror/system/shell/zsh/
Netherlands
ftp://ftp.demon.nl/pub/mirrors/zsh/
Norway
ftp://ftp.uit.no/pub/unix/shells/zsh/
Poland
ftp://sunsite.icm.edu.pl/pub/unix/shells/zsh/
Romania
ftp://ftp.roedu.net/pub/mirrors/ftp.zsh.org/pub/zsh/
ftp://ftp.kappa.ro/pub/mirrors/ftp.zsh.org/pub/zsh/
Slovenia
ftp://ftp.siol.net/mirrors/zsh/
Sweden
ftp://ftp.lysator.liu.se/pub/unix/zsh/
UK
ftp://ftp.net.lut.ac.uk/zsh/
ftp://sunsite.org.uk/packages/zsh/
USA
ftp://uiarchive.uiuc.edu/mirrors/ftp/ftp.zsh.org/pub/
ftp://ftp.rge.com/pub/shells/zsh/
http://zsh.disillusion.org/
http://foad.org/zsh/
The up-to-date source code is available via anonymous CVS
from Sourceforge. See http://sourceforge.net/projects/zsh/
for details.
MAILING LISTS
Zsh has 3 mailing lists:
<zsh-announce@sunsite.dk>
Announcements about releases, major changes in the
shell and the monthly posting of the Zsh FAQ.
(moderated)
<zsh-users@sunsite.dk>
User discussions.
<zsh-workers@sunsite.dk>
Hacking, development, bug reports and patches.
To subscribe or unsubscribe, send mail to the associated
administrative address for the mailing list.
<zsh-announce-subscribe@sunsite.dk>
<zsh-users-subscribe@sunsite.dk>
<zsh-workers-subscribe@sunsite.dk>
<zsh-announce-unsubscribe@sunsite.dk>
<zsh-users-unsubscribe@sunsite.dk>
<zsh-workers-unsubscribe@sunsite.dk>
YOU ONLY NEED TO JOIN ONE OF THE MAILING LISTS AS THEY ARE
NESTED. All submissions to zsh-announce are automatically
forwarded to zsh-users. All submissions to zsh-users are
automatically forwarded to zsh-workers.
If you have problems subscribing/unsubscribing to any of the
mailing lists, send mail to <listmaster@zsh.org>. The mail-
ing lists are maintained by Karsten Thygesen
<karthy@kom.auc.dk>.
The mailing lists are archived; the archives can be accessed
via the administrative addresses listed above. There is
also a hypertext archive, maintained by Geoff Wing
<gcw@zsh.org>, available at http://www.zsh.org/mla/.
THE ZSH FAQ
Zsh has a list of Frequently Asked Questions (FAQ), main-
tained by Peter Stephenson <pws@zsh.org>. It is regularly
posted to the newsgroup comp.unix.shell and the zsh-announce
mailing list. The latest version can be found at any of the
Zsh FTP sites, or at http://www.zsh.org/FAQ/. The contact
address for FAQ-related matters is <faqmaster@zsh.org>.
THE ZSH WEB PAGE
Zsh has a web page which is located at http://www.zsh.org/.
This is maintained by Karsten Thygesen <karthy@zsh.org>, of
SunSITE Denmark. The contact address for web-related
matters is <webmaster@zsh.org>.
THE ZSH USERGUIDE
A userguide is currently in preparation. It is intended to
complement the manual, with explanations and hints on issues
where the manual can be cabbalistic, hierographic, or down-
right mystifying (for example, the word `hierographic' does
not exist). It can be viewed in its current state at
http://zsh.sunsite.dk/Guide/. At the time of writing,
chapters dealing with startup files and their contents and
the new completion system were essentially complete.
THE ZSH WIKI
A `wiki' website for zsh has been created at
http://www.zshwiki.org/. This is a site which can be added
to and modified directly by users without any special per-
mission. You can add your own zsh tips and configurations.
INVOCATION OPTIONS
The following flags are interpreted by the shell when
invoked to determine where the shell will read commands
from:
-c Take the first argument as a command to execute, rather
than reading commands from a script or standard input.
If any further arguments are given, the first one is
assigned to $0, rather than being used as a positional
parameter.
-i Force shell to be interactive.
-s Force shell to read commands from the standard input.
If the -s flag is not present and an argument is given,
the first argument is taken to be the pathname of a
script to execute.
After the first one or two arguments have been appropriated
as described above, the remaining arguments are assigned to
the positional parameters.
For further options, which are common to invocation and the
set builtin, see zshoptions(1).
Options may be specified by name using the -o option. -o
acts like a single-letter option, but takes a following
string as the option name. For example,
zsh -x -o shwordsplit scr
runs the script scr, setting the XTRACE option by the
corresponding letter `-x' and the SH_WORD_SPLIT option by
name. Options may be turned off by name by using +o instead
of -o. -o can be stacked up with preceding single-letter
options, so for example `-xo shwordsplit' or
`-xoshwordsplit' is equivalent to `-x -o shwordsplit'.
Options may also be specified by name in GNU long option
style, `--option-name'. When this is done, `-' characters
in the option name are permitted: they are translated into
`_', and thus ignored. So, for example, `zsh
--sh-word-split' invokes zsh with the SH_WORD_SPLIT option
turned on. Like other option syntaxes, options can be
turned off by replacing the initial `-' with a `+'; thus
`+-sh-word-split' is equivalent to `--no-sh-word-split'.
Unlike other option syntaxes, GNU-style long options cannot
be stacked with any other options, so for example
`-x-shwordsplit' is an error, rather than being treated like
`-x --shwordsplit'.
The special GNU-style option `--version' is handled; it
sends to standard output the shell's version information,
then exits successfully. `--help' is also handled; it sends
to standard output a list of options that can be used when
invoking the shell, then exits successfully.
Option processing may be finished, allowing following argu-
ments that start with `-' or `+' to be treated as normal
arguments, in two ways. Firstly, a lone `-' (or `+') as an
argument by itself ends option processing. Secondly, a spe-
cial option `--' (or `+-'), which may be specified on its
own (which is the standard POSIX usage) or may be stacked
with preceding options (so `-x-' is equivalent to `-x --').
Options are not permitted to be stacked after `--' (so
`-x-f' is an error), but note the GNU-style option form dis-
cussed above, where `--shwordsplit' is permitted and does
not end option processing.
Except when the sh/ksh emulation single-letter options are
in effect, the option `-b' (or `+b') ends option processing.
`-b' is like `--', except that further single-letter options
can be stacked after the `-b' and will take effect as nor-
mal.
COMPATIBILITY
Zsh tries to emulate sh or ksh when it is invoked as sh or
ksh respectively; more precisely, it looks at the first
letter of the name by which it was invoked, excluding any
initial `r' (assumed to stand for `restricted'), and if that
is `s' or `k' it will emulate sh or ksh. Furthermore, if
invoked as su (which happens on certain systems when the
shell is executed by the su command), the shell will try to
find an alternative name from the SHELL environment variable
and perform emulation based on that.
In sh and ksh compatibility modes the following parameters
are not special and not initialized by the shell: ARGC,
argv, cdpath, fignore, fpath, HISTCHARS, mailpath, MANPATH,
manpath, path, prompt, PROMPT, PROMPT2, PROMPT3, PROMPT4,
psvar, status, watch.
The usual zsh startup/shutdown scripts are not executed.
Login shells source /etc/profile followed by $HOME/.profile.
If the ENV environment variable is set on invocation, $ENV
is sourced after the profile scripts. The value of ENV is
subjected to parameter expansion, command substitution, and
arithmetic expansion before being interpreted as a pathname.
Note that the PRIVILEGED option also affects the execution
of startup files.
The following options are set if the shell is invoked as sh
or ksh: NO_BAD_PATTERN, NO_BANG_HIST, NO_BG_NICE,
NO_EQUALS, NO_FUNCTION_ARGZERO, GLOB_SUBST,
NO_GLOBAL_EXPORT, NO_HUP, INTERACTIVE_COMMENTS, KSH_ARRAYS,
NO_MULTIOS, NO_NOMATCH, NO_NOTIFY, POSIX_BUILTINS,
NO_PROMPT_PERCENT, RM_STAR_SILENT, SH_FILE_EXPANSION,
SH_GLOB, SH_OPTION_LETTERS, SH_WORD_SPLIT. Additionally the
BSD_ECHO and IGNORE_BRACES options are set if zsh is invoked
as sh. Also, the KSH_OPTION_PRINT, LOCAL_OPTIONS,
PROMPT_BANG, PROMPT_SUBST and SINGLE_LINE_ZLE options are
set if zsh is invoked as ksh.
RESTRICTED SHELL
When the basename of the command used to invoke zsh starts
with the letter `r' or the `-r' command line option is sup-
plied at invocation, the shell becomes restricted. Emula-
tion mode is determined after stripping the letter `r' from
the invocation name. The following are disabled in res-
tricted mode:
o changing directories with the cd builtin
o changing or unsetting the PATH, path, MODULE_PATH,
module_path, SHELL, HISTFILE, HISTSIZE, GID, EGID, UID,
EUID, USERNAME, LD_LIBRARY_PATH, LD_AOUT_LIBRARY_PATH,
LD_PRELOAD and LD_AOUT_PRELOAD parameters
o specifying command names containing /
o specifying command pathnames using hash
o redirecting output to files
o using the exec builtin command to replace the shell
with another command
o using jobs -Z to overwrite the shell process' argument
and environment space
o using the ARGV0 parameter to override argv[0] for
external commands
o turning off restricted mode with set +r or unsetopt
RESTRICTED
These restrictions are enforced after processing the startup
files. The startup files should set up PATH to point to a
directory of commands which can be safely invoked in the
restricted environment. They may also add further restric-
tions by disabling selected builtins.
Restricted mode can also be activated any time by setting
the RESTRICTED option. This immediately enables all the
restrictions described above even if the shell still has not
processed all startup files.
STARTUP/SHUTDOWN FILES
Commands are first read from /etc/zshenv; this cannot be
overridden. Subsequent behaviour is modified by the RCS and
GLOBAL_RCS options; the former affects all startup files,
while the second only affects those in the /etc directory.
If one of the options is unset at any point, any subsequent
startup file(s) of the corresponding type will not be read.
It is also possible for a file in $ZDOTDIR to re-enable
GLOBAL_RCS. Both RCS and GLOBAL_RCS are set by default.
Commands are then read from $ZDOTDIR/.zshenv. If the shell
is a login shell, commands are read from /etc/zprofile and
then $ZDOTDIR/.zprofile. Then, if the shell is interactive,
commands are read from /etc/zshrc and then $ZDOTDIR/.zshrc.
Finally, if the shell is a login shell, /etc/zlogin and
$ZDOTDIR/.zlogin are read.
When a login shell exits, the files $ZDOTDIR/.zlogout and
then /etc/zlogout are read. This happens with either an
explicit exit via the exit or logout commands, or an impli-
cit exit by reading end-of-file from the terminal. However,
if the shell terminates due to exec'ing another process, the
logout files are not read. These are also affected by the
RCS and GLOBAL_RCS options. Note also that the RCS option
affects the saving of history files, i.e. if RCS is unset
when the shell exits, no history file will be saved.
If ZDOTDIR is unset, HOME is used instead. Those files
listed above as being in /etc may be in another directory,
depending on the installation.
As /etc/zshenv is run for all instances of zsh, it is impor-
tant that it be kept as small as possible. In particular,
it is a good idea to put code that does not need to be run
for every single shell behind a test of the form `if [[ -o
rcs ]]; then ...' so that it will not be executed when zsh
is invoked with the `-f' option.
Any of these files may be pre-compiled with the zcompile
builtin command (see zshbuiltins(1)). If a compiled file
exists (named for the original file plus the .zwc extension)
and it is newer than the original file, the compiled file
will be used instead.
FILES
$ZDOTDIR/.zshenv
$ZDOTDIR/.zprofile
$ZDOTDIR/.zshrc
$ZDOTDIR/.zlogin
$ZDOTDIR/.zlogout
${TMPPREFIX}* (default is /tmp/zsh*)
/etc/zshenv
/etc/zprofile
/etc/zshrc
/etc/zlogin
/etc/zlogout (installation-specific - /etc is the default)
SEE ALSO
sh(1), csh(1), tcsh(1), rc(1), bash(1), ksh(1), zshbuil-
tins(1), zshcompwid(1), zshcompsys(1), zshcompctl(1),
zshexpn(1), zshmisc(1), zshmodules(1), zshoptions(1),
zshparam(1), zshzle(1)
IEEE Standard for information Technology - Portable Operat-
ing System Interface (POSIX) - Part 2: Shell and Utilities,
IEEE Inc, 1993, ISBN 1-55937-255-9.
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
_______________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE|
|_______________________________________
| Availability | SUNWzsh |
|_______________________________________
| Interface Stability| External |
|____________________|_________________|
NOTES
Source for zsh is available in the SUNWzshS package.
|
|