Release Notes

Changes since zsh version 4.2.0

• The autoload and related builtins take options -k and -z to indicate ksh or zsh autoloading style for given functions, making it possible to mix and match.
• Assignments to associative arrays can use the i and r index flags. For example,

  assoc[(i)alpha*]=bravo

  sets the value for the element whose key matches the pattern `alpha*';

  assoc[(r)activ*]=passive

  sets the value for the element whose current value matches the pattern `activ*'.
• The glob qualifier F indicates a non-empty directory. Hence *(F) indicates all subdirectories with entries, *(/^F) means all subdirectories with no entries.
• fc -p and fc -P provide push/pop for the status of the shell's history (both internal and using the history file). With automatic scoping (fc -ap) it becomes easy to use a temporary history in a function. This has been added to the calculator function zcalc to make its internal history work more seamlessly.
• A new try block and always block syntax has been introduced to make it easier to ensure the shell runs important tidy-up code in the event of an error. It also runs after a break, continue, or return, including a return forced by the ERR_RETURN option (but not an exit, which is immediate). The syntax is:

  `{'  try-block-list `}' `always' `{' always-block-list `}'

  where no newline or semicolon may appear between `}' and `always'. This is compatible with all previous valid zsh syntax as an `always' at that point used to be a syntax error. For example,

  { echo Code run in current shell } always { echo Tidy-up code }

• A new zle widget reset-prompt has been added to re-expand the current prompt. Changes to the variable in use as well as changes in its expanions are both taken into account. The same effect is now forced by a job change notification, making the %j prompt escape and %(j..) ternary expression more useful.
• The zftp module supports ports following the hostname in the normal suffix notation, `host:port'. This requires IPv6 colon-style addresses to be specified in suitably quoted square brackets, for example:

  zftp open '[f000::baaa]'
  zftp open '[f000::baaa]:ftp'
  

  (the two are equivalent).
• Special traps, those that don't correspond to signals, i.e. ZERR, DEBUG and EXIT are no longer executed inside other traps. This caused unnecessary confusion if, for example, both DEBUG and EXIT traps were set. The new behaviour is more compatible with other shells.
• New option TRAPS_ASYNC which if set allows traps to run while the shell is waiting for a child process. This is the traditional zsh behaviour; POSIX requires the option to be unset. In sh/ksh compatibility mode the option is turned off by default and the option letter -T turns it on, for compatibility with FreeBSD sh.
• New WIDGETSTYLE, WIDGETFUNC parameters in ZLE.
• Glob qualifiers (+func) is shorthand for (e:func:) (calls command, typically shell function, with no argument).

New features between zsh versions 4.0 and 4.2

• upgraded to use autoconf post-2.50
• improved compatibility with other shells through shell options, builtin arguments and improved builtin option parsing

• new printf builtin
• `+=' to append to parameters which works for scalars, arrays and (with pairs) associative arrays.
• enhanced multiple parameter `for' loops: for key value in key1 value1 key2 value2 ... maintaining full compatibility with POSIX syntax.
• Suffix aliases allow the shell to run a command on a file by suffix, e.g `alias -s ps=gv' makes `foo.ps' execute `gv foo.ps'. Supplied function zsh-mime-setup uses existing mailcap and mime.types files to set up suitable aliases. Supplied function pick-web-browser is suitable for finding a browser to show .html etc. files by suffix alias.
• new option `no_case_glob' for case-insensitive globbing.

• zsh/datetime modules makes date formatting and seconds since EPOCH available inside the shell.
• zsh/net/tcp module provides builtin interface to TCP through ztcp builtin. Function suite for interactive and script use with expect-style pattern matching.
• zsh/net/socket module provides zsocket builtin.
• zcalc calculator function with full line editing.
• builtin interface to pcre library
• zsh/zselect module provides zselect builtin as interface to select system call

• general improvements to command and context support, low-level functions, display code.
• in verbose mode, matches with the same description are grouped
• highly configurable completions for values of specific parameters, specific redirections for specific commands
• support for bash completion functions (typically zsh native functions are more powerful where available)
• New completions provided for (some of these may be in later 4.0 releases): valgrind, tidy, texinfo, infocmp, Java classes, larch, limit, locale parameters, netcat, mysqldiff, mt, lsof, elinks, ant, debchange (dch), email addresses, file system types, Perforce, xsltproc. Plus many others.

• special parameters $PREDISPLAY, $POSTDISPLAY available in function widgets to configure uneditable text (for narrowing)
• recursive editing
• supplied widgets read-from-minibuffer, replace-string use these features (more intuitive prompting and argument reading than 4.0)
• access to killed text via $CUTBUFFER and $killring
• supplied highly configurable word widgets forward-word-match etc., can set what constitutes a word interactively or in startup script (implement bash-style behaviour, replacing previous bash-* word widgets)
• interface to incremental search via $LASTSEARCH
• better handling of keymaps in zle and widgets
• better support for output from user-defined widgets while zle is active
• tetris game which runs entirely in zle
• several other contributed widgets

• disowned jobs are automatically restarted
• \u and \U print escapes for Unicode
• read -d allows a custom line ending.
• read -t .
• line numbers in error messages and $PS4 output are more consistent
• `=prog' expands only paths, no longer aliases for consistency
• job display in prompts; `jobs' command output can be piped
• prompts: new $RPROMPT2, %^, %j, %y, enhanced %{, %}, %_.
• rand48() function in zsh/mathfunc for better randomness in arithmetic (if the corresponding math library function is present)
• $SECONDS parameter can be made floating point via `typeset -F SECONDS' for better timing accuracy
• improvements to command line history mechanism
• job table is dynamically sized, preventing overflow (typically seen previously in complex completions).
• many bugfixes

New features in zsh version 4.0.1

• the new completion system — more functions, completers, styles...
• the line editor
• handling of signals and traps
• the configuration system, particularly for modules
• Cygwin support (now essentially complete)
• arithmetic evaluation
• the zpty (pseudoterminal handling) module
• the test suite

The alias modules (zle.so as an alias for zsh/zle.so, etc.) have been removed; use `zmodload -A' to load modules under other names. This is irrelevant if you are upgrading from 3.0.

Compared with the 3.0 series of releases (the last stable set), the most significant of a large number of improvements in the shell are:

• Dynamically loadable modules with hierarchical naming system
• Shell functions as editor functions, with much additional builtin support
• Incredibly rich new completion system; just needs a single initialization command to provide completion for all sorts of commands and contexts
• Associative arrays
• Lots of new features in parameter substitution and globbing; more logical handling of nested parameter substitutions
• Rewritten pattern-matching (globbing) code supports approximate and case-insensitive matching and backreferences
• Various custom modules for pty's, FTP, special parameters, etc.
• Rewrites of many internal parts of the code: execution code to provide compilation to internal representation, pattern matching
• Floating point arithmetic and mathematical functions module
• A test suite
• Various new options for compatibility with this, that and the other

New features in zsh version 3.1.8 and 3.1.9

These are primarily bug-fix versions. There are only a few user-visible changes.

• Array slices ${array[a,b]} with b < a now correctly have zero length.

New features in zsh version 3.1.7

Further enhancements to new completion system:

• Comprehensive context-sensitive configuration via `styles', which can be set by the menu-driven front end in compinstall
• General mechanism for setting patterns to be ignored in a completion; overriding of patterns to be matched for functions
• New completers: _prefix to complete word before cursor, _ignored to complete using words so far ignored (like $fignore but more powerful), _history to complete words from shell history
• Multiple use of completers with different options, similarly splitting of different types of completion (`tags') so they are considered with different styles
• Many more supplied completions for standard commands which work out of the box, and better handling of command line options/arguments which behave in the usual way
• $fpath now set up to use installed functions by default; functions can be loaded just by `autoload -U compinit; compinit'
• Much improved handling of nested quoting and nested braces
• New LIST_PACKED and LIST_ROWS_FIRST completion options and corresponding styles
• compctl library separated out (frozen but still supported)
• User-friendly introduction available at zsh website

Additions to complist listing library (coloured completion and menu selection):

• Listings can be shown page by page (are by default for new completion)
• Menu selection allows full up and down scrolling of long lists

Other editing features:

• new parameters $PENDING, $MARK, $BUFFERLINES
• Easy display of a prompt from within an editing widget

Code parsing, storing and execution:

• Completely new system of storing code internally, greatly optimised
• Much less memory for shell functions etc.
• Can compile shell functions to .zwc `wordcode' functions for fast loading
• Can create `digest' files of entire directories in .zwc format

Parameters:

• Floating point support added, similar to ksh93, `typeset -F' and `typeset -E' declare floating point variables; usual C/Fortran-like rules for integer/float conversion
• Mathematical library zsh/mathfunc contains all the standard mathematical functions for use in arithmetical expressions
• Improved parsing of arithmetical expressions and better error messages
• Special parameters can be made local
• `typeset -h' hides specialness of parameters, either as parameter attribute or when declaring new local variable
• Local parameters can now be exported as in other shells; new option GLOBAL_EXPORTS on by default provides old behaviour that `typeset -x' referred to global parameters.
• zsh/parameter module enhanced: now needed for new completion; parameters provided have `-h' flag set so that they are hidden by `typeset', so that existing functions don't need to be changed
• Quotes can be stripped from parameter values with ${(Q)...}, providing reverse of ${(q...)...} facility

Globbing and pattern matching:

• Pattern matching rewritten for efficiency
• Supports `backreferences', i.e. extracting parenthesised chunks of matches, e.g. [[ $foo = (#b)(*/)[^/]* ]] stores the part of $foo up to the last / in $match[1] and the indexes of the match in $mbegin[1], $mend[1]. (#m) is also available to set $MATCH to the entire match and corresponding $MBEGIN, $MEND: useful in parameter substitutions like ${.../.../...}.
• (#s) and (#e) match start and end of pattern like ^ and $ in regular expression, useful in complex expressions such as ((#s)|/)dirname((#e)|/) and in parameter expressions.
• Depth-first/last listing of recursive glob lists

Functions etc.:

• `autoload -X' inside a function body instructs the shell to bootstrap the function at that point
• `autoload +X fn' says load the function fn but don't execute it
• Prompt `themes' make customization of prompts easier

Modules:

• New hierarchical naming scheme for modules; supplied modules go into zsh subdirectory, so zle becomes zsh/zle etc.; aliases supplied for compatibility for existing code, but the new format should be used in future.
• zmodload is more consistent between dynamically and statically linked shells
• zsh/zftp and its function suite support multiple sessions (zfsession command); zftransfer allows transfer of files between two ftp sessions with no local file; use styles for e.g. progress style; IPv6 supported; recursive put `zfput -r' for uploads
• zsh/zpty module creates pseudoterminal and allows builtin `expect'-like behaviour

Other:

• Test suite, not yet complete (`make test')
• use of Linux task limits
• Many fixes including output redirection with `setopt xtrace' and other redirection fixes; NIS+ problem.
• Better null-command behaviour in sh and csh emulation
• Internal memory usage optimisations

New features in zsh version 3.1.6 (beta version)

Note also the changes for 3.0.6, which include changes between 3.1.5. and 3.1.6.

New completion system via shell functions; massive degree of programmability and configurability:

• ready-made function suite to use, see zshcompsys(1)
• approximate completion and spelling correction via completion
• control over matching for case-independence, partial word completion, etc.
• menu selection: choose a completion by moving the cursor
• coloured completion lists
• completion of filenames in quotes is now more reliable; splitting quoted strings into command arguments is also possible.

Other editing changes:

• enhancements to function/editing interface: new parameters, numeric arguments, string argument passing, reading keys from widgets.
• the old history-search-{back,for}ward behaviour and bindings have returned (up to minor details).
• BASH_AUTO_LIST option to show completion list only on second key press.
• the ZBEEP parameter gives a string to output instead of beeping, allowing you to have a visual bell.

History changes: new options HIST_NO_FUNCTIONS, HIST_EXPIRE_DUPS_FIRST, HIST_FIND_NO_DUPS, HIST_IGNORE_ALL_DUPS, INC_APPEND_HISTORY, HIST_SAVE_NO_DUPS, SHARE_HISTORY, allow better control of when history is read and written and how duplicates are handled. New format for history saves.

Associative arrays plus enhanced parameter substitutions to retrieve keys and values.

Globbing changes:

• Case-insensitive and approximate globbing.
• Ordering and indexing of globbing matches, e.g. *(om[1]) picks most recently modified file.
• General file mode qualifier with chmod(1)-like syntax, e.g. *(f:u+wx:)

New loadable modules:

• zftp, plus associated function suite, for turning your zsh session into an FTP session too
• parameter, for examining and altering shell hash tables via an associative array interface.
• mapfile, for reading and writing external files via an associative array interface.

Debugging and prompt enhancements:

• $PS4 can contain %i for $LINENO as well as %N for script or function names (default PS4 changed), also %_ for current shell structure executing;
• Prompt truncation %<...< is now more flexible: it applies to a whole section of the prompt, not just one escape. You need to put %<< after the truncated escape to get the old behaviour.
• %20(l.yes.no) in prompts prints yes if at least 20 characters have been output, else no (e.g. for outputting extra newlines).

Parameter and expansion changes

• `typeset -t MYPATH mypath' creates tied path/PATH-like variables
• `typeset -g' allows operations on parameters without making them local
• New expansions
  • ${(t)param} prints type information for $param
  • ${(P)param} treats value of $param as the name of a param to substitute
  • ${foo:q} can quote replaced parameter text from expansion
  • ${foo/old/new} substitution, like bash; also (S) flag for shortest match
  • $foo[(b.2.i)bar] starts searching $foo for bar starting at 2nd match

Builtin and function changes

• stat module: `stat -H hash foo' gives you e.g. $hash[mtime]
• `autoload -U' autoloads functions without alias expansion.

Other new options:

• LOCAL_TRAPS allows signal traps to be local to functions (as in ksh).
• NO_RCS can now be turned on at any point in initialization files.
• NO_GLOBAL_RCS can force /etc/z* files after /etc/zshenv to be skipped. (Please don't use this as an excuse to stuff more into /etc/zshenv!)
• Existing MAGIC_EQUAL_SUBST option is more useful; any argument containing ...=~...:~... will perform filename expansion on the ~ (previously, the string before `=' had to look like a parameter name).

Configuration changes:

• Generation of signal names should be more reliable
• Customizable installation of shell functions from distribution.

New features in zsh version 3.0.6

Most of these changes are designed to improve compatibility with zsh version 3.1.6, the latest development release. However, this release also fixes all known Year 2000 (Y2K) bugs in zsh 3.0.

History changes:

• whitespace between words is ignored in history searches.
• new option HIST_REDUCE_BLANKS removes extra whitespace in the stored history.
• support for reading (but not writing) version 3.1.6 history files.

Globbing changes:

• the a, c, and m glob qualifiers can now test time in seconds.
• globbing of number ranges behaves more like character ranges in that it can match a prefix of a number, e.g. `<1-5>*' matches 1, 2, 3, 4, 5, 17, 23skiddoo, 5986, etc., but not 6, 7, 8ball, 911, etc.

Parameter and expansion changes:

• expansion of ~ and other globbing flags via ${~param} do not depend upon EXTENDED_GLOB (bug fix).
• nested parameter substitutions require braces (this was always the documented behavior, but previous parsers didn't enforce it).
• quote only nested expansion, e.g. ${(f)"$(<file)"} reads complete `file', then splits lines into array.

Builtin and function changes:

• `typeset -U' works on the colon-array version of linked parameters.
• `typeset +f' and `functions +' output the names (only) of functions.
• `emulate -L' has the effect of `setopt localoptions'.
• in fn1() { local foo; unset foo; foo=bar; }, foo is restored at local level, whereas if the `unset foo' appeared in a nested function it would have been restored at global level, which was presumably wrong.
• `foo=bar >&file' is a redirection, not a NULLCMD.
• any single complex command, such as `case ... esac', parses as if semicolon-terminated (bug fix).
• the shell function `preexec', if defined, is run after parsing each command line but before executing the command.

Other changes:

• the option PRINT_EIGHT_BIT causes zsh to emit raw bytes in prompts and completion lists even if the system ctype(3) package says that those bytes are not "printable."

Debugging enhancements:

• LINENO is now very much more useful in scripts and functions and is reported correctly in most error messages.
• ERREXIT behavior is now consistent with newer Bourne-like shells, e.g. with respect to `if' tests that fail.

Configuration changes:

• Large file and 64-bit integers on 32-bit machines supported where provided by OS.
• a few more system features, such as getpwnam/getpwuid, are tested for.

New features in zsh version 3.1 (beta version)

On most operating systems zsh can load binary modules dynamically at run-time. ZLE and the compctl builtin are now reside in a separate module which is loaded automatically on demand.

for ((expr; expr; expr)) do ... done loop syntax from AT&T ksh93 is now supported.

POSIX globbing character classes ([:alnum:] etc.) are now supported.

ksh's case fall-through feature (;&) is supported.

ksh93's $'' quoting syntax is supported.

Restricted mode is now supported. This is controlled by the new option RESTRICTED (-r).

New options BARE_GLOB_QUAL, HIST_NO_FUNCTIONS (alias NO_LOG), KSH_GLOB, PRINT_EIGHT_BIT, PROMPT_BANG, PROMPT_PERCENT, RM_STAR_WAIT.

Options ALWAYS_LAST_PROMPT, APPEND_HISTORY, AUTO_LIST, AUTO_MENU, AUTO_PARAM_KEYS, AUTO_PARAM_SLASH, AUTO_REMOVE_SLASH, LIST_AMBIGUOUS and LIST_TYPES are now on by default.

In ZLE, arbitrarily many keymaps can be defined. Multi-character keybindings now work.

Completion can be performed within a brace expansion.

EMACS-like universal-argument function.

New features in zsh version 3.0

Trailing "/" in a glob pattern now works like in other shell thus it can no longer be used as a shorthand for "(/)".

Much improved sh/ksh emulation. When zsh is invoked as sh it mostly conforms to POSIX 1003.2.

Enhanced parameter expansion features: new flags: A, @, e, W, p, f, F. Expansions can be nested. For example, "${${(M)${(f@)$(<builtin.pro)}:#char*}[2][(w)3]}" expands to the third word of the second line of builtin.pro which begins with char. See zshexpn(1) for the details.

***/foo glob does recursive directory search following symbolic links.

Traps defined by the trap builtin are now executed in the current shell environment and not as a shell function. This means that $1 is not set to the signal number. Of course the TRAPxxx functions continue working as before.

Traps defined by the trap builtin are reset to their default values in subshells.

Option names can be prefixed by `no' to unset an option. setopt no_option_name is the same as unsetopt option_name. This change affects the output of the setopt and unsetopt builtins when these are invoked without arguments. See the zshoptions manual page for more explanation.

!, {, } and [[ are now reserved words. Things like [[-z $foo]] or {foo} should not be used. {foo} still works if the IGNORE_BRACES option is not set but this feature may be removed in the future. [[ -z $foo ]] and { foo } should be used instead.

HOSTTYPE special parameter is removed. The new OSTYPE, MACHTYPE and VENDOR parameters should be used instead.

VERSION parameter is renamed to ZSH_VERSION

exec now saves the history in interactive shells. If you do not like this behaviour you can alias exec to 'unset HISTFILE ; exec'.

${~spec}, ${=spec} and ${^spec} used to toggle the effect of globsubst/shwordsplit/rcexpandparam. Now these force the corresponding option on. ~, = or ^ can be doubled to force the relevant option off for the substitution.

Explicitly requested word splitting like ${=spec} or ${(s:delim:)spec} will be executed even if the substitution is double quoted.

The right-hand side of assignments are no longer globbed by default hence assignment foo=* will assign '*' as a value of foo. Use the foo=( * ) array assignment syntax to get the old behaviour. Alternatively the GLOB_ASSIGN can be set to emulate the old behaviour but the usage of this option is strongly discouraged and this option may be completely removed in the future.

foo=$bar no longer creates an array even if bar is an array. Use foo=( $bar ) or even better, foo=( "$bar[@]" ) instead.

When foo is an array parameter ${#foo} will always return the length of the array even if the substitution is double quoted. ${(c)#foo} should be used to get back the old behaviour.

When the prompt_subst option is set prompts are fully expanded using parameter expansion, command substitution and arithmetic expansion. In 2.5 backquote substitution was not performed in the prompts so this change might cause problems in some startup scripts if ` is used literally in prompts.

History substitution is now not performed if the history escape character appears in a single-quoted string. This may break some interactive shell functions which use \! in single-quoted strings.

The UID, EUID, GID, EGID parameters can be assigned now. The assignment executes the setuid(), seteuid(), setgid(), setegid() respectively. On systems where setuid and seteuid is not supported these functions are emulated using setreuid or setresuid which may result in a different behaviour.

Assigning the USERNAME parameter will call setuid(uid) where uid is the user id of the specified user.

The privileged (-p) option is automatically set on invocation if euid != uid or egid != gid. If this option is set no user startup files are sourced. The shell will drop privileges when this option is unset by resetting its euid to uid and its egid to gid.

The =number substitution for accessing the directory stack is changed to ~number to allow =command substitution when a command name begins with a digit.

<> is a redirection operator which opens the standard input for both reading and writing. To match a number use <->

Option letters -1 and -C for PRINT_EXIT_VALUE and NO_CLOBBER are swapped: `set -C' sets NO_CLOBBER and `set -1' sets PRINT_EXIT_VALUE.

AUTO_PUSHD behaviour is changed. Now cd without arguments will always go to the $HOME directory even if AUTO_PUSHD is set and PUSHD_TO_HOME is not set. If you preferred the old behaviour you can alias cd to pushd.

IFS word splitting with SH_WORD_SPLIT and the splitting of the input in the read builtin has changed in cases when IFS contains characters other than <space>, <tab>, <newline>. See the description of IFS in the zshparam manual page for more details.

New features in zsh version 2.5

Greatly expanded completion possibilities. Programmable completion allows detailed control over what arguments of what commands can be completed to what. See dots/zcomp in the distribution for examples.

Expand filenames with ~ and = on the right hand side of parameter assignments. New option MAGIC_EQUAL_SUBST to do it in all identifier=expression arguments.

${+name} becomes 1 or 0 if name is set or unset. ${~spec} toggles GLOB_SUBST in substitution. Parameter substitution takes lots of flags in the format ${(flags)name}.

New glob qualifiers for block/character special files, times in glob qualifiers can be in months, weeks, days, hours, minutes. Qualifiers can work on links or on what they point to. Qualifiers separated by commas are or-ed.

New parameter substitution modifiers (fFwW) to repeat actions. New option CSH_JUNKIE_HISTORY.

New line editor functions history-beginning-search-backward, history-beginning-search-forward, expand-or-complete-prefix, push-input, push-line-or-edit.

Assign to part of a string, use qualifiers on string subscription with $foo[(qual)2,5]

New parameters: EGID, EUID, KEYTIMEOUT

New prompt escape sequence %_ to get constructs like for and while in the secondary prompt. %E in prompt clears to end of screen.

Conditional expressions in PROMPT and WATCHFMT.

New options ALWAYS_LAST_PROMPT, ALWAYS_TO_END, AUTO_PARAM_KEYS, COMPLETE_ALIASES, COMPLETE_IN_WORD, CSH_JUNKIE_HISTORY, GLOB_SUBST, LIST_AMBIGUOUS, MAGIC_EQUAL_SUBST, NO_FLOW_CONTROL, PROMPT_SUBST

New option -m to many builtins makes arguments subject to pattern matching.

Bindkey can now bind both key sequences and prefixes of those. You can for example bind ESC and function keys sending ESC sequences.

Additional options to read builtin to use in functions called by completion.

New options to print to sort arguments and print them in columns.

Some additional resource limits can be specified.

Some editor functions now work in the minibuffer.