ZSH

NAME

zsh - the Z shell

SYNOPSIS

zsh [ ±options ] [ ±o option ] ... [ -c string ] [ arg ... ]

SHELL GRAMMAR

A simple command is a sequence of optional parameter assignments followed by blank-separated words, with optional redirections interspersed. The first word is the command to be executed, and the remaining words, if any, are arguments to the command. If a command name is given, the parameter assignments modify the environment of the command when it is executed. The value of a simple command is its exit status, or 128 plus the signal number if terminated by a signal.

If a simple command is preceded by the word exec, it is executed in the parent shell without forking. If preceded by command, the command word is taken to be the name of an external command, rather than a shell function or builtin. If preceded by noglob, filename generation is not performed on any of the words. If preceded by a -, the command is executed with a - prepended to its argv[0] string. If preceded by nocorrect, spelling correction is not done on any of the words.

A pipeline is a sequence of one or more commands separated by | or |&. |& is shorthand for 2>&1 |. The standard output of each command is connected to the standard input of the next command in the pipeline.

The value of a pipeline is the value of the last command. If a pipeline is preceded by a !, the value of that pipeline is the logical NOT of the value of the last command.

If a pipeline is preceded by coproc, it is executed as a coprocess; a two-way pipe is established between it and the parent shell. The shell can read from or write to the coprocess by means of the >&p and <&p redirection operators.

A sublist is a sequence of one or more pipelines separated by && or ||. If two pipelines are separated by &&, the second pipeline is executed only if the first is successful (returns a zero value). If two pipelines are separated by ||, the second is executed only if the first is unsuccessful (returns a nonzero value).

A list is a sequence of one or more sublists separated by, and optionally terminated by, ;, &, or a newline. Normally the shell waits for each list to finish before executing the next one. If a list is terminated by a &, the shell executes it in the background, and does not wait for it to finish.

A complex command is one of the following:

for name [ in word ... ]
do list

for name [ in word ... ] ; sublist

This is a shorthand for for. Though it may cause confusion, it is included for convenience; its use in scripts is discouraged, unless sublist is a command of the form { list }.

foreach name ( word ... )

for name in word ...

for name ( word ... ) {

for name ( word ... ) sublist

Another form of for.

select name [ in word ... ]
do list

select name [ in word ] ; sublist

A short form of select.

case word in [ pattern ) list ;; ] ... esac

Execute the list associated with the first pattern that matches word, if any. The form of the patterns is the same as that used for filename generation. See Filename Generation below.

case word { [ pattern ) list ;; ] ... }

Another form of case.

if list
then list
[ elif list ; then list ] ...
[ else list ]

if ( list ) sublist

A short form of if.

if ( list ) {

} elif ( list ) {

} ... else {

while list
do list

while ( list ) {

until list
do list

repeat word
do list

repeat word sublist

This is a short form of repeat.

( list )

Execute list in a subshell.

{ list }

Execute list.

function word [ () ] ... { list }
word ... () { list }
word ... () sublist

Define a function which is referenced by any one of word. Normally, only one word is provided; multiple words are usually only useful for setting traps. The body of the function is the list between the { and }. See FUNCTIONS below.

time [ pipeline ]

The pipeline is executed, and timing statistics are reported on the standard error in the form specified by the TIMEFMT parameter. If pipeline is omitted, print statistics about the shell process and its children.

[[ exp ]]

Evaluates the conditional expression exp and return a zero exit status if it is true. See Conditional Expressions below for a description of exp.

RESERVED WORDS

The following words are recognized as reserved words when used as the first word of a command unless quoted or removed using the unalias builtin:

do done esac then elif else fi for case if while function repeat time until exec command select coproc noglob - nocorrect foreach end

COMMENTS

In noninteractive shells, or in interactive shells with the INTERACTIVE_COMMENTS option set, a word beginning with the third character of the HISTCHARS parameter (’#’ by default) causes that word and all the following characters up to a newline to be ignored.

ALIASING

Every token in the shell input is checked to see if there is an alias defined for it. If so, it is replaced by the text of the alias if it is in command position (if it could be the first word of a simple command), or if the alias is global. If the text ends with a space, the next word in the shell input is treated as though it were in command position for purposes of alias expansion. An alias is defined using the alias builtin; global aliases may be defined using the -g option to that bulitin.

Alias substitution is done on the shell input before any other substitution except history substitution. Therefore, if an alias is defined for the word foo, alias substitution may be avoided by quoting part of the word, e.g. \foo. But there is nothing to prevent an alias being defined for \foo as well.

QUOTING

A character may be quoted (that is, made to stand for itself) by preceding it with a \. \ followed by a newline is ignored. All characters enclosed between a pair of single quotes (’’) are quoted. A single quote cannot appear within single quotes. Inside double quotes (""), parameter and command substitution occurs, and \ quotes the characters \, ’, ", and $.

EXPANSION

Expansion is performed on the command line after it has been parsed. The types of expansions performed are filename expansion, process substitution, parameter expansion, command substitution, arithmetic expansion, brace expansion, and filename generation.

Filename Expansion
Each word is checked to see if it begins with an unquoted ~. If it does, then the word up to a / is checked to see if it matches the name of a named directory. If so, then the ~ and the matched portion are replaced with the value of the named directory. A ~ by itself or followed by a / is replaced by the value of the HOME parameter. A ~ followed by a + or a - is replaced by the value of PWD or OLDPWD, respectively.

Named directories are typically login directories for users on the system. They may also be defined if the text after the ~ is the name of a string shell parameter whose value begins with a /. In certain circumstances (in prompts, for instance), when the shell prints a path, the path is checked to see if it has a named directory as its prefix. If so, then the prefix portion is replaced with a ~ followed by the name of the directory. The longest match is preferred.

If a word begins with an unquoted = and the NO_EQUALS option is not set, the remainder of the word is taken as the name of a command or alias. If a command exists by that name, the word is replaced by the full pathname of the command. If an alias exists by that name, the word is replaced with the text of the alias. Otherwise the word is checked up to a / to see if it is a number or a -. If so, the matched portion is replaced with the nth directory in the directory stack, where n is the number matched, or the last directory in the directory stack if a - is matched.

Process Substitution
Each command argument of the form <(list) or >(list) or =(list) is subject to process substitution. In the case of the < or > forms, the shell will run process list asynchronously connected to a named pipe (FIFO). The name of this pipe will become the argument to the command. If the form with > is selected then writing on this file will provide input for list. If < is used, then the file passed as an argument will be a named pipe connected to the output of the list process. For example,

paste <(cut -f1 file1) <(cut -f3 file2) | tee >(process1) >(process2) >/dev/null

cuts fields 1 and 3 from the files file1 and file2 respectively, pastes the results together, and sends it to the processes process1 and process2. Note that the file, which is passed as an argument to the command, is a system pipe so programs that expect to lseek(2) on the file will not work. Also note that the previous example can be more compactly and efficiently written as:

paste <(cut -f1 file1) <(cut -f3 file2) > >(process1) > >(process2)

The shell uses pipes instead of FIFOs to implement the latter two process substitutions in the above example.

If = is used, then the file passed as an argument will be the name of a temporary file containing the output of the list process. This may be used instead of the < form for a program that expects to lseek(2) on the input file.

Parameter Expansion
The character $ is used to introduce parameter expansions. See PARAMETERS below for a description of parameters.

${name}

The value, if any, of the parameter name is substituted. The braces are required if name is followed by a letter, digit, or underscore that is not to be interpreted as part of its name. If name is an array parameter, then the values of each element of name is substituted, one element per word. Otherwise, the expansion results in one word only; no word splitting is done on the result.

${name:-word}

If name is set and is non-null then substitute its value; otherwise substitute word.

${name:=word}

If name is unset or is null then set it to word; the value of the parameter is then substituted.

${name:?word}

If name is set and is non-null, then substitute its value; otherwise, print word and exit from the shell. If word is omitted, then a standard message is printed.

${name:+word}

If name is set and is non-null then substitute word; otherwise substitute nothing.

${name#pattern}
${name##pattern}

If the pattern matches the beginning of the value of name, then substitute the value of name with the matched portion deleted; otherwise, just substitute the value of name. In the first form, the smallest matching pattern is preferred; in the second form, the largest matching pattern is preferred.

${name%pattern}
${name%%pattern}

If the pattern matches the end of the value of name, then substitute the value of name with the matched portion deleted; otherwise, just substitute the value of name. In the first form, the smallest matching pattern is preferred; in the second form, the largest matching pattern is preferred.

${#spec}

If spec is one of the above substitutions, substitute the length in characters of the result instead of the result itself. If spec is an array expression, substitute the number of elements of the result.

${^spec}

Toggle the value of the RC_EXPAND_PARAM option for the evaluation of spec. When this option is set, array expansions of the form foo${xx}bar, where the parameter xx is set to (a b c), are substituted with fooabar foobbar foocbar instead of the default fooa b cbar.

${=spec}

Toggle the value of the SH_WORD_SPLIT option for the evaluation of spec. When this option is set, parameter values are split into separate words using IFS as a delimiter before substitution. This is done by default in most other shells.

If the colon is omitted from one of the above expressions containing a colon, then the shell only checks whether name is set or not, not whether it is null.

Command Substitution
A command enclosed in parentheses preceded by a dollar sign, like so: $(...) or quoted with grave accents: ’...’ is replaced with its standard output. If the substitution is not enclosed in double quotes, the output is broken into words using the IFS parameter. The substitution $(cat foo) may be replaced by the equivalent but faster $(<foo).

Arithmetic Expansion
A string of the form $[exp] is substituted with the value of the arithmetic expression exp. exp is treated as if it were within single quotes. See ARITHMETIC EVALUATION below.

Brace Expansion
A string of the form foo{xx,yy,zz}bar is expanded to the individual words fooxxbar, fooyybar, and foozzbar. Left-to-right order is preserved. This construct may be nested. Malformed brace expansion expressions, including expressions without a comma, are left unchanged by the shell.

An expression of the form {x-y}, where x and y are single characters, is expanded to every character between x and y, inclusive.

Filename Generation
If a word contains an unquoted instance of one of the characters *, |, <, [, or ?, it is regarded as a pattern for filename generation, unless the NOGLOB option is set. If the EXTENDED_GLOB option is set, the ^ and # characters also denote a pattern; otherwise they are not treated specially by the shell. The word is replaced with a list of sorted filenames that match the pattern. If no matching pattern is found, the shell gives an error message, unless the NULLGLOB option is set, in which case the word is deleted; or unless the NO_NOMATCH option is set, in which case the word is left unchanged. In filename generation, the character / must be matched explicitly; also, a . must be matched explicitly at the beginning of a pattern or after a /, unless the GLOBDOTS option is set. No filename generation pattern matches the files "." or "..". In other instances of pattern matching, the / and . are not treated specially.

[ ... ]

matches any of the enclosed characters.

[^ ... ]

matches any character except the enclosed characters.

Parentheses may be used for grouping. Note that the | character must be within parentheses, so that the lexical analyzer does not think it is a pipe character. Also note that "/" has a higher precedence than "^"; that is:

ls ^foo/bar

will search directories in "." except "./foo" for a file named bar.

A pathname component of the form (foo/)# matches a path consisting of zero or more directories matching the pattern foo. As a shorthand, **/ is equivalent to (*/)#. Thus:

ls (*/)#bar

or

ls **/bar

does a recursive directory search for files named bar.

If used for filename generation, a pattern may contain an exclusion specifier. Such patterns are of the form pat1~pat2. This pattern will generate all files matching pat1, but which do not match pat2. For example, *.c~lex.c will match all files ending in .c, except the file lex.c.

Patterns used for filename generation may also end in a list of qualifiers enclosed in parentheses. The qualifiers specify which filenames that otherwise match the given pattern will be inserted in the argument list. A qualifier may be any one of the following:

a[-|+]n

files accessed within last n days (-), more than n days ago (+), or n days ago.

m[-|+]n

files modified within last n days (-), more than n days ago (+), or n days ago.

c[-|+]n

files whose inode changed within last n days (-), more than n days ago (+), or n days ago.

L[+|-]n

files less than n bytes (-), more than n bytes (+), or exactly n bytes in length.

Thus:

ls *(%W)

lists all world-writable device files in the current directory, and

ls /tmp/foo*(u0^@)

lists all root-owned files beginning with the string "foo" in /tmp, ignoring symlinks, and

ls *.*~(lex|parse).[ch](^D^l1)

lists all files having a link count of one whose names contain a dot (but not those starting with a dot, since GLOBDOTS is explicitly switched off) except for lex.c, lex.h, parse.c, and parse.h. A "/" at the end of a pattern is equivalent to "(/)".

REDIRECTION

Before a command is executed, its input and output may be redirected. The following may appear anywhere in a simple-command or may precede or follow a complex command. Substitution occurs before word is used except as noted below. If the result of substitution on word produces more than one filename, redirection occurs for each separate filename in turn.

>! word

Same as >, except that the file is truncated to zero length if it exists, even if NOCLOBBER is set.

>>! word

Same as >>, except that the file is created if it does not exist, even if NOCLOBBER is set.

<<[-] word

The shell input is read up to a line that is the same as word, or to an end-of-file. No parameter substitution, command substitution or filename generation is performed on word. The resulting document, called a here-document, becomes the standard input. If any character of word is quoted with single or double quotes or a \, no interpretation is placed upon the characters of the document. Otherwise, parameter and command substitution occurs, \ followed by a newline is removed, and \ must be used to quote the characters \, $, ’, and the first character of word. If <<- is used, then all leading tabs are stripped from word and from the document.

<<<word

Open a file containing word, after expansion, as standard input.

<&digit

The standard input is duplicated from file descriptor digit (see dup(2)). Similarly for standard output using >&digit.

>>&word

Same as >>word 2>&1.

If one of the above is preceded by a digit, then the file descriptor referred to is that specified by the digit (instead of the default 0 or 1). The order in which redirections are specified is significant. The shell evaluates each redirection in terms of the (file descriptor, file) association at the time of evaluation. For example:

... 1>fname 2>&1

first associates file descriptor 1 with file fname. It then associates file descriptor 2 with the file associated with file descriptor 1 (that is, fname). If the order of redirections were reversed, file descriptor 2 would be associated with the terminal (assuming file descriptor 1 had been) and then file descriptor 1 would be associated with file fname.

If the user tries to open a file descriptor for writing more than once, the shell opens the file descriptor as a pipe to a process that copies its input to all the specified outputs, similar to tee(1). Thus:

date >foo >bar

writes the date to two files, named "foo" and "bar". Note that a pipe is an implicit indirection; thus

date >foo | cat

writes the date to the file "foo", and also pipes it to cat.

If the user tries to open a file descriptor for reading more than once, the shell opens the file descriptor as a pipe to a process that copies all the specified inputs to its output in the order specified, similar to cat(1). Thus

sort <foo <fubar

or even

sort <f{oo,ubar}

is equivalent to "cat foo bar | sort". Note that a pipe is in implicit indirection; thus

cat bar | sort <foo

is equivalent to "cat bar foo | sort" (note the order of the inputs).

If a simple command consists of one or more redirection operators and zero or more parameter assignments, but no command name, the command cat is assumed. Thus

< file

prints the contents of file.

If a command is followed by & and job control is not active, then the default standard input for the command is the empty file /dev/null. Otherwise, the environment for the execution of a command contains the file descriptors of the invoking shell as modified by input/output specifications.

COMMAND EXECUTION

If a command name contains no slashes, the shell attempts to locate it. If there exists a shell function by that name, the function is invoked as described below in FUNCTIONS. If there exists a shell builtin by that name, the builtin is invoked.

Otherwise, the shell searches each element of path for a directory containing an executable file by that name. If the search is unsuccessful, the shell prints an error message and returns a nonzero exit status.

If execution fails because the file is not in executable format, and the file is not a directory, it is assumed to be a shell script. /bin/sh is spawned to execute it. If the program is a file beginning with #!, the remainder of the first line specifies an interpreter for the program. The shell will execute the specified interpreter on operating systems that do not handle this executable format in the kernel.

FUNCTIONS

The function reserved word is used to define shell functions. Shell functions are read in and stored internally. Alias names are resolved when the function is read. Functions are executed like commands with the arguments passed as positional parameters. (See Execution below).

Functions execute in the same process as the caller and share all files and present working directory with the caller. A trap on EXIT set inside a function is executed after the function completes in the environment of the caller.

The return builtin is used to return from function calls.

Function identifiers can be listed with the functions builtin. Functions can be undefined with the unfunction builtin.

The following functions, if defined, have special meaning to the shell:

periodic

If the parameter PERIOD is set, this function is executed every PERIOD seconds, just before a prompt.

TRAPxxx

If defined and non-null, this function will be executed whenever the shell catches a signal SIGxxx, where xxx is a signal name as specified for the kill builtin (see below). In addition, TRAPERR is executed whenever a command has a non-zero exit status, TRAPDEBUG is executed after each command, and TRAPEXIT is executed when the shell exits, or when the current function exits if defined inside a function. If a function of this form is defined and null, the shell and processes spawned by it will ignore SIGxxx.

JOBS

If the MONITOR option is set, an interactive shell associates a job with each pipeline. It keeps a table of current jobs, printed by the jobs command, and assigns them small integer numbers. When a job is started asynchronously with &, the shell prints a line which looks like:

[1] 1234

indicating that the job which was started asynchronously was job number 1 and had one (top-level) process, whose process id was 1234.

If you are running a job and wish to do something else you may hit the key ^Z (control-Z) which sends a STOP signal to the current job. The shell will then normally indicate that the job has been ’suspended’, and print another prompt. You can then manipulate the state of this job, putting it in the background with the bg command, or run some other commands and then eventually bring the job back into the foreground with the foreground command fg. A ^Z takes effect immediately and is like an interrupt in that pending output and unread input are discarded when it is typed.

A job being run in the background will suspend if it tries to read from the terminal. Background jobs are normally allowed to produce output, but this can be disabled by giving the command ’’stty tostop’’. If you set this tty option, then background jobs will suspend when they try to produce output like they do when they try to read input.

There are several ways to refer to jobs in the shell. A job can be referred to by the process id of any process of the job or by one of the following:
%number

The job with the given number.

%string

Any job whose command line begins with string.

%?string

Any job whose command line contains string.

The shell learns immediately whenever a process changes state. It normally informs you whenever a job becomes blocked so that no further progress is possible. If notify is not set, it waits until just before it prints a prompt before it informs you.

When the monitor mode is on, each background job that completes triggers any trap set for CHLD.

When you try to leave the shell while jobs are running or suspended, you will be warned that ’You have suspended (running) jobs.’ You may use the jobs command to see what they are. If you do this or immediately try to exit again, the shell will not warn you a second time; the suspended jobs will be terminated, and the running jobs will be sent a SIGHUP signal. To avoid having the shell terminate the running jobs, either use the nohup(1) command or the disown builtin (see below).

SIGNALS

The INT and QUIT signals for an invoked command are ignored if the command is followed by & and the job monitor option is not active. Otherwise, signals have the values inherited by the shell from its parent (but see the TRAPxxx special function above).

HISTORY

History substitution allows you to use words from previous command lines in the command line you are typing. This simplifies spelling corrections and the repetition of complicated commands or arguments. Command lines are saved in the history list, the size of which is controlled by the HISTSIZE variable. The most recent command is retained in any case. A history substitution begins with a ! and may occur anywhere on the command line; history substitutions do not nest. The ! can be escaped with \ to suppress its special meaning. Single or double quotes will not work for this.

Input lines containing history substitutions are echoed on the terminal after being expanded, but before any other substitutions take place or the command gets executed.

Event Designators
An event designator is a reference to a command-line entry in the history list.

!?str[?]

Refer to the most recent command containing str.

Word Designators
A ’:’ separates the event specification from the word designator. It can be omitted if the word designator begins with a , $, *, - or %. If the word is to be selected from the previous command, the second ! character can be omitted from the event specification. For instance, !!:1 and !:1 both refer to the first word of the previous command, while !!$ and !$ both refer to the last word in the previous command. Word designators include:

Modifiers
After the optional word designator, you can add a sequence of one or more of the following modifiers, each preceded by a :. These modifiers also work on the result of filename and parameter expansion.

s/l/r[/]

Substitute r for l.

Unless preceded by a g, the substitution is done only for the first string that matches l.

The left-hand side of substitutions are not regular expressions, but character strings. Any character can be used as the delimiter in place of /. A backslash quotes the delimiter character. The character &, in the right hand side, is replaced by the text from the left-hand-side. The & can be quoted with a backslash. A null l uses the previous string either from a l or from a contextual scan string s from !?s. You can omit the rightmost delimiter if a newline immediately follows r; the rightmost ? in a context scan can similarly be omitted.

Without an event specification, a history reference refers either to the previous command, or to a previous history reference on the command line (if any).

The character sequence ^foo^bar repeats the last command, replacing the string "foo" with the string "bar".

If the shell encounters the character sequence !" in the input, the history mechanism is temporarily disabled until the current list is fully parsed. The !" is removed from the input, and any subsequent ! characters have no special significance.

A less convenient but more comprehensible form of command history support is provided by the fc builtin (see below).

ARITHMETIC EVALUATION

An ability to perform integer arithmetic is provided with the builtin let. Evaluations are performed using long arithmetic. Constants are of the form [base#]n where base is a decimal number between two and thirty-six representing the arithmetic base and n is a number in that base. If base is omitted then base 10 is used.

An arithmetic expression uses nearly the same syntax, precedence, and associativity of expressions in C. The following operators are supported (listed in decreasing order of precedence):

+ - ! ∼ ++ --

unary plus/minus, logical NOT, complement, {pre,post}{in,de}crement

< > <= >=

comparison

= += -= *= /= %= &= ^= |= <<= >>= &&= ||= ^^=

assignment

The operators &&, ||, &&=, and ||= are short-circuiting, and only one of the latter two expressions in a ternary operator is evaluated. Note the precedence of the logical AND, OR, and XOR operators.

Named parameters can be referenced by name within an arithmetic expression without using the parameter substitution syntax.

An internal integer representation of a named parameter can be specified with the integer builtin. Arithmetic evaluation is performed on the value of each assignment to a named parameter declared integer in this manner.

Since many of the arithmetic operators require quoting, an alternative form of the let command is provided. For any command which begins with a ((, all the characters until a matching )) are treated as a quoted expression. More precisely, ((...)) is equivalent to let "...".

CONDITIONAL EXPRESSIONS

A conditional expression is used with the [[ compound command to test attributes of files and to compare strings. Each expression can be constructed from one or more of the following unary or binary expressions:
-a file

true if file exists.

-b file

true if file exists and is a block special file.

-c file

true if file exists and is a character special file.

-d file

true if file exists and is a directory.

-e file

true if file exists.

-f file

true if file exists and is an ordinary file.

-g file

true if file exists and has its setgid bit set.

-h file

true if file exists and is a symbolic link.

-k file

true if file exists and has its sticky bit set.

-n string

true if length of string is non-zero.

-o option

true if option named option is on.

-p file

true if file exists and is a fifo special file or a pipe.

-r file

true if file exists and is readable by current process.

-s file

true if file exists and has size greater than zero.

-u file

true if file exists and has its setuid bit set.

-w file

true if file exists and is writable by current process.

-x file

true if file exists and is executable by current process. If file exists and is a directory, then the current process has permission to search in the directory.

-z string

true if length of string is zero.

-L file

true if file exists and is a symbolic link.

-O file

true if file exists and is owned by the effective user id of this process.

-G file

true if file exists and its group matches the effective group id of this process.

-S file

true if file exists and is a socket.

file1 -nt file2

true if file1 exists and is newer than file2.

file1 -ot file2

true if file1 exists and is older than file2.

file1 -ef file2

true if file1 and file2 exist and refer to the same file.

string = pattern

true if string matches pattern.

string != pattern

true if string does not match pattern.

string1 < string2

true if string1 comes before string2 based on ASCII value of their characters.

string1 > string2

true if string1 comes after string2 based on ASCII value of their characters.

exp1 -eq exp2

true if exp1 is equal to exp2.

exp1 -ne exp2

true if exp1 is not equal to exp2.

exp1 -lt exp2

true if exp1 is less than exp2.

exp1 -gt exp2

true if exp1 is greater than exp2.

exp1 -le exp2

true if exp1 is less than or equal to exp2.

exp1 -ge exp2

true if exp1 is greater than or equal to exp2.

( exp )

true if exp is true.

exp1 && exp2

true if exp1 and exp2 are both true.

exp1 || exp2

true if either exp1 or exp2 is true.

In each of the above expressions, if file is of the form /dev/fd/n, where n is an integer, then the test applied to the open file whose descriptor number is n, even if the underlying system does not support the /dev/fd directory.

ZSH LINE EDITOR

If the ZLE option is set (it is by default) and the shell input is attached to the terminal, the user is allowed to edit command lines.

There are two display modes. The first, multiline mode, is the default. It only works if the TERM parameter is set to a valid terminal type that can move the cursor up. The second, single line mode, is used if TERM is invalid or incapable of moving the cursor up, or if the SINGLE_LINE_ZLE option is set. This mode is similar to ksh, and uses no termcap sequences.

Bindings
Command bindings may be set using the bindkey builtin. There are two keymaps-the main keymap and the alternate keymap. The alternate keymap is bound to vi command mode. The main keymap is bound to emacs mode by default. To bind the main keymap to vi insert mode, use bindkey -v, or set one of the VISUAL or EDITOR environment variables to a string containing vi.

The following is a list of all the key commands and their default bindings in emacs and vi command mode.

Movement
vi-backward-blank-word (unbound) (B)

Move backward one word, where a word is defined as a series of non-blank characters.

backward-char (^B ESC-[D) ()

Move backward one character.

vi-backward-char () (h)

Move backward one character, without changing lines.

backward-word (ESC-B ESC-b) (unbound)

Move to the beginning of the previous word.

emacs-backward-word

Move to the beginning of the previous word.

vi-backward-word (unbound) (b)

Move to the beginning of the previous word, vi-style.

beginning-of-line (^A) (0)

Move to the beginning of the line. If already at the beginning of the line, move to the beginning of the previous line, if any.

vi-beginning-of-line

Move to the beginning of the line, without changing lines.

end-of-line (^E)

Move to the end of the line. If already at the end of the line, move to the end of the next line, if any.

vi-end-of-line (unbound) ($)

Move to the end of the line.

vi-forward-blank-word (unbound) (W)

Move forward one word, where a word is defined as a series of non-blank characters.

vi-forward-blank-word-end (unbound) (E)

Move to the end of the current word, or, if at the end of the current word, to the end of the next word, where a word is defined as a series of non-blank characters.

forward-char (^F ESC-[C)

Move forward one character.

vi-forward-char (unbound) (space l)

Move forward one character.

vi-find-next-char (^X^F) (f)

Read a character from the keyboard, and move to the next occurrence of it in the line.

vi-find-next-char-skip (unbound) (t)

Read a character from the keyboard, and move to the position just before the next occurrence of it in the line.

vi-find-prev-char (unbound) (F)

Read a character from the keyboard, and move to the previous occurrence of it in the line.

vi-find-prev-char-skip (unbound) (T)

Read a character from the keyboard, and move to the position just after the previous occurrence of it in the line.

vi-first-non-blank (unbound) (^)

Move to the first non-blank character in the line.

vi-forward-word (unbound) (w)

Move forward one word, vi-style.

forward-word (ESC-F ESC-f) (unbound)

Move to the beginning of the next word. The editor’s idea of a word is specified with the WORDCHARS parameter.

emacs-forward-word

Move to the end of the next word.

vi-forward-word-end (unbound) (e)

Move to the end of the next word.

vi-goto-column (ESC-|) (|)

Move to the column specified by the numeric argument.

vi-goto-mark (unbound) (’)

Move to the specified mark.

vi-goto-mark-line (unbound) (’)

Move to beginning of the line containing the specified mark.

vi-repeat-find (unbound) (;)

Repeat the last vi-find command.

vi-rev-repeat-find (unbound) (,)

Repeat the last vi-find command in the opposite direction.

History
beginning-of-buffer-or-history (ESC-<)

Move to the beginning of the buffer, or if already there, move to the first event in the history list.

beginning-of-line-hist

Move to the beginning of the line. If already at the beginning of the buffer, move to the previous history line.

beginning-of-history

Move to the first event in the history list.

down-line-or-history (^N ESC-[B) (+ j)

Move down a line in the buffer, or if already at the bottom line, move to the next event in the history list.

down-line-or-search

Move down a line in the buffer, or if already at the bottom line, search forward in the history for a line beginning with the first word in the buffer.

down-history (unbound) (^N)

Move to the next event in the history list.

end-of-buffer-or-history (ESC->)

Move to the end of the buffer, or if already there, move to the last event in the history list.

end-of-line-hist

Move to the end of the line. If already at the end of the buffer, move to the next history line.

end-of-history

Move to the last event in the history list.

vi-fetch-history (unbound) (G)

Fetch the history line specified by the numeric argument.

history-incremental-search-backward (^R ^Xr)

Search backward incrementally for a specified string. The string may begin with ’^’ to anchor the search to the beginning of the line.

history-incremental-search-forward (^Xs)

Search forward incrementally for a specified string. The string may begin with ’^’ to anchor the search to the beginning of the line.

history-search-backward (ESC-P ESC-p) (K)

Search backward in the history for a line beginning with the first word in the buffer.

vi-history-search-backward (unbound) (/)

Search backward in the history for a specified string. The string may begin with ’^’ to anchor the search to the beginning of the line.

history-search-forward (ESC-N ESC-n) (J)

Search forward in the history for a line beginning with the first word in the buffer.

vi-history-search-forward (unbound) (?)

Search forward in the history for a specified string. The string may begin with ’^’ to anchor the search to the beginning of the line.

infer-next-history (^X^N)

Search in the history list for a line matching the current one and fetch the event following it.

insert-last-word (ESC-_ ESC-.)

Insert the last word from the previous history event at the cursor position.

vi-repeat-search (unbound) (n)

Repeat the last vi history search.

vi-rev-repeat-search (unbound) (N)

Repeat the last vi history search, but in reverse.

toggle-literal-history (ESC-R ESC-r)

Toggle between literal and lexical history. The default is lexical history unless the HISTLIT option is set.

up-line-or-history (^P ESC-[A) (- k)

Move up a line in the buffer, or if already at the top line, move to the previous event in the history list.

up-line-or-search

Move up a line in the buffer, or if already at the top line, search backward in the history for a line beginning with the first word in the buffer.

up-history (unbound) (^P)

Move to the previous event in the history list.

Modifying Text
vi-add-eol (unbound) (A)

Move to the end of the line and enter insert mode.

vi-add-next (unbound) (a)

Move forward one character and enter insert mode.

backward-delete-char (^H ^?) (^?)

Delete the character behind the cursor.

vi-backward-delete-char (unbound) (X)

Delete the character behind the cursor, without changing lines.

backward-delete-word

Delete the word behind the cursor.

backward-kill-line

Kill from the beginning of the line to the cursor position.

backward-kill-word (^W ESC-^H ESC-^?)

Kill the word behind the cursor.

vi-backward-kill-word (unbound) (^W)

Kill the word behind the cursor.

capitalize-word (ESC-C ESC-c)

Capitalize the current word and move past it.

vi-change (unbound) (c)

Read a movement command from the keyboard, and kill from the cursor position to the endpoint of the movement. Then enter insert mode. If the command is vi-change, kill the current line.

vi-change-eol (unbound) (C)

Kill to the end of the line and enter insert mode.

vi-change-whole-line (unbound) (S s)

Kill the current line and enter insert mode.

copy-region-as-kill (ESC-W ESC-w)

Copy the area from the cursor to the mark to the kill buffer.

copy-prev-word (ESC-^_)

Duplicate the word behind the cursor.

vi-delete (unbound) (d)

Read a movement command from the keyboard, and kill from the cursor position to the endpoint of the movement. If the command is vi-delete, kill the current line.

delete-char (unbound) (x)

Delete the character under the cursor.

vi-delete-char (unbound) (x)

Delete the character under the cursor.

delete-word (ESC-D ESC-d)

Delete the current word.

down-case-word (ESC-L ESC-l)

Convert the current word to all lowercase and move past it.

kill-word

Kill the current word.

gosmacs-transpose-chars

Exchange the two characters behind the cursor.

vi-indent (unbound) (>)

Indent a number of lines.

vi-insert (unbound) (i)

Enter insert mode.

vi-insert-bol (unbound) (I)

Move to the beginning of the line and enter insert mode.

vi-join (^X^J)

Join the current line with the next one.

kill-line (^K) (D)

Kill from the cursor to the end of the line.

kill-region

Kill from the cursor to the mark.

kill-buffer (^X^U) (^U)

Kill the entire buffer.

kill-whole-line (^U) (unbound)

Kill the current line.

vi-match-bracket (^X^B) (%)

Move to the bracket character (one of {}, (), or []) that matches the one under the cursor.

vi-open-line-above (unbound) (O)

Open a line above the cursor and enter insert mode.

vi-open-line-below (unbound) (o)

Open a line below the cursor and enter insert mode.

vi-oper-swap-case

Read a movement command from the keyboard, and swap the case of all characters from the cursor position to the endpoint of the movement. If the movement command is vi-oper-swap-case, swap the case of all characters on the current line.

overwrite-mode (^X^O)

Toggle between overwrite mode and insert mode.

vi-put-after (unbound) (p)

Insert the contents of the kill buffer after the cursor.

quoted-insert (^V)

Insert the next character typed into the buffer literally.

quote-line (ESC-’)

Quote the current line; that is, put a ’ character at the beginning and the end, and convert all ’ characters to ’\’’.

quote-region (ESC-")

Quote the region from the cursor to the mark.

vi-replace (unbound) (R)

Enter overwrite mode.

vi-repeat-change (unbound) (.)

Repeat the last vi mode text modification.

vi-replace-chars (unbound) (r)

Replace the character under the cursor with a character read from the keyboard.

self-insert (printable characters)

Put a character in the buffer at the cursor position.

self-insert-unmeta (ESC-^I ESC-^J ESC-^M)

Put a character in the buffer after stripping the meta bit and converting ^M to ^J.

vi-substitute (unbound) (s)

Substitute the next character(s).

vi-swap-case (unbound) (~)

Swap the case of the character under the cursor and move past it.

transpose-chars (^T)

Exchange the two characters to the left of the cursor if at end of line, else exchange the character under the cursor with the character to the left.

transpose-words (ESC-T ESC-t)

Exchange the current word with the one before it.

vi-unindent (unbound) (<)

Unindent a number of lines.

up-case-word (ESC-U ESC-u)

Convert the current word to all caps and move past it.

yank (^Y) (P)

Insert the contents of the kill buffer at the cursor position.

yank-pop (ESC-y) (unbound)

Remove the text just yanked, rotate the kill-ring, and yank the new top. Only works following yank or yank-pop.

vi-yank (unbound) (y)

Read a movement command from the keyboard, and copy the region from the cursor position to the endpoint of the movement into the kill buffer. If the command is vi-yank, copy the current line.

vi-yank-eol (unbound) (Y)

Copy the region from the cursor position to the end of the line into the kill buffer.

Arguments
digit-argument (ESC-0..ESC-9) (0-9)

Start a new numeric argument, or add to the current one.

universal-argument

Multiply the argument of the next command by 4.

Completion
accept-and-menu-complete

In a menu completion, insert the current completion into the buffer, and advance to the next possible completion.

complete-word (unbound) (\)

Attempt completion on the current word.

delete-char-or-list (^D)

Delete the character under the cursor. If the cursor is at the end of the line, list possible completions for the current word.

execute-named-cmd (ESC-x)

Read the name of a editor command and execute it.

execute-last-named-cmd (ESC-z)

Redo the last function executed with execute-named-cmd.

expand-cmd-path

Expand the current command to its full pathname.

expand-or-complete (TAB) (TAB ^X)

Attempt shell expansion on the current word. If that fails, attempt completion.

expand-history (ESC-space ESC-!)

Perform history expansion on the edit buffer.

expand-word (^X*)

Attempt shell expansion on the current word.

list-choices (ESC-^D) (^D =)

List possible completions for the current word.

list-expand (^Xg ^XG) (^G)

List the expansion of the current word.

magic-space

Perform history expansion and insert a space into the buffer. This is intended to be bound to space.

menu-complete

Like complete-word, except that menu completion is used. See the MENU_COMPLETE option below.

menu-expand-or-complete

Like expand-or-complete, except that menu completion is used.

reverse-menu-complete

See the MENU_COMPLETE option below.

Miscellaneous
accept-and-hold (ESC-A ESC-a)

Push the contents of the buffer on the buffer stack and execute it.

accept-and-infer-next-history

Execute the contents of the buffer. Then search the history list for a line matching the current one and push the event following onto the buffer stack.

accept-line (^J ^M)

Execute the contents of the buffer.

accept-line-and-down-history (^O)

Execute the current line, and push the next history event on the the buffer stack.

vi-cmd-mode (^X^V) (^[)

Enter command mode; that is, use the alternate keymap. Yes, this is bound by default in emacs mode.

vi-caps-lock-panic (unbound) (H K)

Hang until any lowercase key is pressed. This is for vi users without the mental capacity to keep track of their caps lock key (like the author).

clear-screen (^L ESC-^L)

Clear the screen and redraw the prompt.

exchange-point-and-mark (^X^X)

Exchange the cursor position with the position of the mark.

get-line (ESC-G ESC-g)

Pop the top line off the buffer stack and insert it at the cursor position.

pound-insert (unbound) (#)

If there is no # character at the beginning of the current line, add one. If there is one, remove it. In either case, accept the current line. The INTERACTIVE_COMMENTS option must be set for this to have any usefulness.

push-line (^Q ESC-Q ESC-q)

Push the current buffer onto the buffer stack and clear the buffer. Next time the editor starts up, the buffer will be popped off the top of the buffer stack and loaded into the editing buffer.

redisplay (unbound) (^R)

Redisplays the edit buffer.

run-help (ESC-H ESC-h)

Push the buffer onto the buffer stack, and execute the command "run-help cmd", where cmd is the current command. run-help is normally aliased to man.

send-break (^C)

Abort the parsing of the current line.

vi-set-buffer (unbound) (")

Specify a buffer to be used in the following command.

vi-set-mark (unbound) (m)

Set the specified mark at the cursor position.

set-mark-command (^@)

Set the mark at the cursor position.

spell-word (ESC-$ ESC-S ESC-s)

Attempt spelling correction on the current word.

undefined-key

Beep.

undo (^_ ^X^U) (u)

Incrementally undo the last text modification.

which-command (ESC-?)

Push the buffer onto the buffer stack, and execute the command "which-command cmd", where cmd is the current command. which-command is normally aliased to whence.

PARAMETERS

A parameter has a name, a value, and a number of attributes. A name may be any sequence of alphanumeric characters and _’s, or the single characters *, @, #, ?, -, $, or !. The value may be either a scalar (a string), an integer, or an array. To assign a scalar or integer value to a parameter, use the typeset builtin. To assign an array value, use set -A name value .... The value of a parameter may also be assigned by writing:

name=value ...

If the integer attribute, -i, is set for name, the value is subject to arithmetic evaluation.

The value of an array parameter may be assigned by writing:

name=(value ...) ...

Individual elements of an array may be selected using a subscript. A subscript of the form [exp] selects the single element exp, where exp is an arithmetic expression. The elements are numbered beginning with 1. A subscript of the form [*] or [@] evaluates to all elements of an array; there is no difference between the two except when they appear within double quotes. "$foo[*]" evaluates to "$foo[1] $foo[2] ...", while "$foo[@]" evaluates to "$foo[1]" "$foo[2]", etc. A subscript of the form [exp1,exp2] selects all elements in the range exp1 to exp2, inclusive. If one of the subscripts evaluates to a negative number, say -n, then the nth element from the end of the array is used. Thus "$foo[-3]" is the third element from the end of the array foo, and "$foo[1,-1]" is the same as "$foo[*]".

Subscripting may also be performed on non-array values, in which case the subscripts specify a substring to be extracted. For example, if FOO is set to foobar, then echo $FOO[2,5] prints ooba.

Positional Parameters
Positional parameters are set by the shell on invocation, by the set builtin, or by direct assignment. The parameter n, where n is a number, is the nth positional parameter. The parameters *, @, and argv are arrays containing all the positional parameters; thus argv[n], etc. is equivalent to simply n.

Special Parameters
The following parameters are automatically set by the shell:

HOSTTYPE

A string corresponding to the type of the host the shell is running on.

SECONDS

The number of seconds since shell invocation. If this parameter is assigned a value, then the value returned upon reference will be the value that was assigned plus the number of seconds since the assignment.

signals

An array containing the names of the signals.

USERNAME
LOGNAME

The username corresponding to the user id of the shell process.

VERSION

The version number of this zsh.

The following parameters are used by the shell:

bindcmds

An write-only array of command names which take line editor function names as arguments, and which therefore should allow binding completion.

cdpath (CDPATH)

An array (colon-separated list) of directories specifying the search path for the cd command.

COLUMNS

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

DIRSTACKSIZE

The maximum size of the directory stack. If the stack gets larger than this, it will be truncated automatically. This is useful with the AUTO_PUSHD option.

fignore (FIGNORE)

An array (colon separated list) containing the suffixes of files to be ignored during filename completion.

fpath (FPATH)

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

HISTCHARS

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

HISTFILE

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

HISTSIZE

The maximum size of the history list.

hostcmds

An write-only array of command names which take hostnames as arguments, and which should therefore allow hostname completion. This sort of completion is also used in words containing a @ character.

hosts (HOSTS)

An array (colon separated list) of hostnames to use for hostname completion.

LISTMAX

In the line editor, the number of filenames to list without asking first.

LITHISTSIZE

The maximum size of the literal history list (before history expansion).

LOGCHECK

The interval in seconds between checks for login/logout activity using the watch parameter.

MAILCHECK

The interval in seconds between checks for new mail.

mailpath (MAILPATH)

An array (colon-separated list) of filenames to check for new mail. Each filename can be followed by a ? and a message that will be printed. The sequence $_ in the message will be replaced by the name of the mail file. The default message is "You have new mail."

manpath (MANPATH)

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

NULLCMD

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

optcmds

An write-only array of commands which take options as arguments, and which therefore should allow option completion.

path (PATH)

An array (colon-separated list) of directories to search for commands. When this parameter is set, each directory is scanned and all files found are put in a hash table.

POSTEDIT

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

%d

%S (%s)

Start (stop) standout mode.

%U (%u)

Start (stop) underline mode.

%B (%b)

Start (stop) boldface mode.

%D{string}

string is formatted using the strftime function. See strftime(3) for more details, if your system has it.

%{...%}

Include a string as a literal escape sequence. The string within the braces should not change the cursor position.

PROMPT2

The secondary prompt, printed when the shell needs more information to complete a command. Recognizes the same escape sequences as $PROMPT. The default is "> ".

PROMPT3

Selection prompt used within a select loop. Recognizes the same escape sequences as $PROMPT. The default is "?# ".

PROMPT4

The execution trace prompt. Default is "+ ".

psvar (PSVAR)

An array (colon-separated list) whose first nine values can be used in PROMPT strings. Setting psvar also sets PSVAR, and vice versa.

READNULLCMD

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

REPORTTIME

If nonzero, commands whose combined user and system execution times (measured in seconds) are greater than this value have timing statistics printed for them.

RPROMPT

SAVEHIST

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

SPROMPT

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

TIMEFMT

The format of process time reports with the time keyword. The default is "%E real %U user %S system %P". Recognizes the following escape sequences:

If this parameter is nonzero, the shell will terminate if a command is not entered within the specified number of seconds after issuing a prompt.

TMPPREFIX

A pathname prefix which the shell will use for all temporary files.

varcmds

An write-only array of command names which take parameter names as arguments, and which therefore should allow parameter completion.

watch (WATCH)

An array (colon-separated list) of login/logout events to report. If it contains the single word "all", then all login/logout events are reported. If it contains the single word "notme", then all events are reported as with "all" except $USERNAME. An entry in this list may consist of a username, an ’@’ followed by a remote hostname, and a ’%’ followed by a line (tty). Any or all of these components may be present in an entry; if a login/logout event matches all of them, it is reported.

WATCHFMT

The format of login/logout reports if the watch parameter is set. Default is "%n has %a %l from %m." Recognizes the following escape sequences:

%S (%s)

Start (stop) standout mode.

%U (%u)

Start (stop) underline mode.

%B (%b)

Start (stop) boldface mode.

WORDCHARS

A list of nonalphanumeric characters considered part of a word by the line editor.

ZDOTDIR

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

OPTIONS

The following options may be set upon invocation of the shell, or with the set or setopt builtins:

ALLEXPORT (-a)

All parameters subsequently defined are automatically exported.

APPEND_HISTORY

If this is set, zsh sessions will append their history list to the history file, rather than overwrite it. Thus, multiple parallel zsh sessions will all have their history lists added to the history file, in the order they are killed.

AUTO_CD (-J)

If a command is not in the hash table, and there exists an executable directory by that name, perform the cd command to that directory.

AUTOLIST (-9)

Automatically list choices on an ambiguous completion.

AUTOMENU

Automatically use menu completion if the TAB key is pressed repeatedly.

AUTO_PUSHD (-N)

Make cd act like pushd.

AUTO_REMOVE_SLASH

When the last character resulting from a completion is a slash and the next character typed is a word delimiter, remove the slash.

AUTO_RESUME (-W)

Treat single word simple commands without redirection as candidates for resumption of an existing job.

BGNICE (-6)

Run all background jobs at a lower priority. This option is set by default.

BRACECCL

Allow brace expansions of the form {a-zA-Z}, etc.

CDABLEVARS (-T)

If the argument to a cd command is not a directory, but a parameter exists by the same name whose value begins with a /, try to change to the directory specified by the parameter’s value.

CHASELINKS (-w)

Resolve symbolic links to their true values.

CORRECT (-0)

Try to correct the spelling of commands.

CORRECT_ALL (-O)

Try to correct the spelling of all arguments in a line.

CSH_JUNKIE_LOOPS

Allow loop bodies to take the form "list; end" instead of "do list; done".

CSH_JUNKIE_QUOTES

Complain if a quoted expression runs off the end of a line; prevent quoted expressions from containing unescaped newlines.

CSH_NULL_GLOB

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

ERREXIT (-e)

If a command has a non-zero exit status, execute the ERR trap, if set, and exit.

EXTENDED_GLOB

Treat the # and ^ characters as part of patterns for filename generation, etc.

EXTENDED_HISTORY

Save beginning and ending timestamps to the history file. The format of these timestamps is :<beginning time>:<ending time>:<command>.

GLOB_COMPLETE

Like MENU_COMPLETE, except that the current word is expanded using normal shell expansion instead of completion. If no matches are found, a * is added to the end of the word, and expansion is attempted again.

GLOB_DOTS (-4)

Do not require a leading . in a filename to be matched explicitly.

HASH_CMDS

Place the location of each command in the hash table the first time it is executed. If this option is unset, no path hashing will be done at all.

HASH_DIRS

Whenever a command is executed, hash the directory containing it, as well as all directories that occur earlier in the path. Has no effect if HASH_CMDS is unset.

HASH_LIST_ALL

Whenever a command completion is attempted, make sure the entire command path is hashed first. This makes the first completion slower.

HIST_IGNORE_DUPS (-h)

Do not enter command lines into the history list if they are duplicates of the previous event.

HIST_IGNORE_SPACE (-g)

Do not enter command lines into the history list if they begin with a blank.

HISTLIT (-j)

Use literal (unparsed) versions of the history lines in the editor.

HIST_NO_STORE

Remove the history (fc -l) command from the history when invoked.

HIST_VERIFY

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

IGNORE_BRACES (-I)

Do not perform brace expansion.

IGNOREEOF (-7)

Do not exit on end-of-file. Require the use of exit or logout instead.

INTERACTIVE (-i)

This is an interactive shell.

INTERACTIVE_COMMENTS (-k)

Allow comments even in interactive shells.

KSH_OPTION_PRINT

Alters the way options settings are printed.

LIST_TYPES (-X)

When listing files that are possible completions, show the type of each file with a trailing identifying mark.

LOGIN (-l)

This is a login shell.

LONG_LIST_JOBS (-R)

List jobs in the long format by default.

MAIL_WARNING (-U)

Print a warning message if a mail file has been accessed since the shell last checked.

MARKDIRS (-8)

Append a trailing / to all directory names resulting from filename generation (globbing).

MENU_COMPLETE (-Y)

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

MENU_COMPLETE_BEEP

Beep on an ambiguous menu completion.

MONITOR (-m)

Allow job control. Set by default in interactive shells.

NO_BAD_PATTERN (-2)

If a pattern for filename generation is badly formed, leave it unchanged in the argument list instead of printing an error.

NO_BANG_HIST (-K)

Do not perform textual history substitution. Do not treat the ! character specially.

NOBEEP (-B)

Do not beep.

NO_CLOBBER (-1)

Prevents > redirection from truncating existing files. >! may be used to truncate a file instead. Also prevents >> from creating files. >>! may be used instead.

NO_EQUALS

Don’t perform = filename substitution.

NOEXEC (-n)

Read commands and check them for syntax errors, but do not execute them.

NOGLOB (-F)

Disable filename generation.

NO_HIST_BEEP

Don’t beep when an attempt is made to access a history entry which isn’t there.

NO_LIST_BEEP

Don’t beep on an ambiguous completion.

NO_NOMATCH (-3)

If a pattern for filename generation has no matches, leave it unchanged in the argument list instead of printing an error.

NO_PROMPT_CR (-V)

Don’t print a carriage return just before printing a prompt in the line editor.

NO_RCS (-f)

Source only the /etc/zshenv file. Do not source the .zshenv, /etc/zprofile, .zprofile, /etc/zshrc, .zshrc, /etc/zlogin, .zlogin, or .zlogout files.

NO_SHORT_LOOPS

Disallow the short forms of for, select, if, and function constructs.

NOTIFY (-5)

Report the status of background jobs immediately, rather than waiting until just before printing a prompt.

NOUNSET (-u)

Treat unset parameters as an error when substituting.

NULLGLOB (-G)

If a pattern for filename generation has no matches, delete the pattern from the argument list instead of reporting an error. Overrides NO_NOMATCH.

NUMERICGLOBSORT

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

OVERSTRIKE

Start up the line editor in overstrike mode.

PATH_DIRS (-Q)

Perform a path search even on command names with slashes in them. Thus if "/usr/local/bin" is in the user’s path, and he types "X11/xinit", the command "/usr/local/bin/X11/xinit" will be executed (assuming it exists).

PRINT_EXIT_VALUE (-C)

Print the exit value of programs with non-zero exit status.

PUSHD_IGNORE_DUPS

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

PUSHD_MINUS

See popd below.

PUSHD_SILENT (-E)

Do not print the directory stack after pushd or popd.

PUSHD_TO_HOME (-D)

Have pushd with no arguments act like pushd $HOME.

RC_EXPAND_PARAM (-P)

See Parameter Expansion.

RC_QUOTES

Allow the character sequence ’’ to signify a single quote within singly quoted strings.

RECEXACT (-S)

In completion, recognize exact matches even if they are ambiguous.

RMSTARSILENT (-H)

Do not query the user before executing "rm *" or "rm path/*".

SHINSTDIN (-s)

Read commands from the standard input.

SH_WORD_SPLIT (-y)

See Parameter Expansion.

SINGLE_LINE_ZLE (-M)

Use single-line command line editing instead of multi-line.

SUN_KEYBOARD_HACK (-L)

If a line ends with a backquote, and there are an odd number of backquotes on the line, ignore the trailing backquote. This is useful on some keyboards where the return key is too small, and the backquote key lies annoyingly close to it.

VERBOSE (-v)

Print shell input lines as they are read.

XTRACE (-x)

Print commands and their arguments as they are executed.

ZLE (-Z)

Use the zsh line editor.

SHELL BUILTIN COMMANDS

. file [ arg ... ]

Read and execute commands from file in the current shell environment. If file does not contain a slash, the shell looks in the components of path to find the directory containing file. If any arguments arg are given, they become the positional parameters; the old positional parameters are restored when the file is done executing. The exit status is the exit status of the last command executed.

: [ arg ... ]

This command only expands parameters. A zero exit code is returned.

alias [ -g ] [ name[=value] ] ...

With no arguments, print the list of aliases in the form name=value on the standard output. For each name with a corresponding value, define an alias with that value. A trailing space in value causes the next word to be checked for alias substitution. If the -g flag is present, define a global alias; global aliases are expanded even if they do not occur in command position. For each name with no value, print the value of name, if any. The exit status is nonzero if a name (with no value) given for which no alias has been defined.

autoload [ name ... ]

For each of the names (which are names of functions), create a function marked undefined. The fpath variable will be searched to find the actual function definition when the function is first referenced.

bg [ job ... ]
job ... &

Put each specified job in the background, or the current job if none is specified.

bindkey -mevd
bindkey -r in-string ...
bindkey [ -a ] in-string [ command ] ...
bindkey -s [ -a ] in-string out-string ...

If one of the -e, -v, or -d options is given, reset the keymaps for emacs mode, vi mode, or the default mode, respectively; if the -m option is also given, allow the use of a meta key. If the -r option is given, remove any binding for each in-string. If the -s option is not specified, bind each in-string to a specified command. If no command is specified, print the binding of in-string if it is bound, or return a nonzero exit code if it is not bound. If the -s option is specified, bind each in-string to each specified out-string. When in-string is typed, out-string will be pushed back and treated as input to the line editor. If the -a option is specified, bind the in-strings in the alternative keymap instead of the standard one. The alternative keymap is used in vi command mode.

For either in-string or out-string, control characters may be specified in the form ^X, and the backslash may be used to introduce one of the following escape sequences:

In all other cases, \ escapes the following character. Delete is written as ’^?’.

break [ n ]

Exit from an enclosing for, while, until, select, or repeat loop. If n is specified, then break n levels instead of just one.

builtin name [ args ] ...

Executes the builtin name, with the given args.

cd [ arg ]
cd old new

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

The third form of cd is equivalent to popd.

compctl [ -cfhovbCD ] [ -k name ] [ arg ... ]

Control the editor’s completion behavior when one of arg is the current command. With the -D flag, control default completion behavior for commands not assigned any special behavior; with -C, control completion when there is no current command. The remaining options specify the type of command arguments to look for during completion. For example, compctl -h rlogin is equivalent to hostcmds=(rlogin).

-k name

Expect names taken from the elements of $name.

continue [ num ]

Resume the next iteration of the enclosing for, while, until, select, or repeat loop. If n is specified, break out of n - 1 loops and resume at the nth enclosing loop.

declare [ arg ... ]

Same as typeset.

dirs [ -v ] [ arg ... ]

With no arguments, print the contents of the directory stack. If the -v option is given, number the directories in the stack when printing. Directories are added to this stack with the pushd command, and removed with the cd or popd commands. If arguments are specified, load them onto the directory stack, replacing anything that was there, and push the current directory onto the stack.

disable arg ...

Disable the builtin arg temporarily. This allows you to use an external command with the same name as a shell builtin. Actually the same as unhash. Builtins can be enabled with the enable command.

disown job ...

Remove the specified jobs from the job table; the shell will no longer report their status, and will not complain if you try to exit an interactive shell with them running or stopped.

echo [ -n ] [ arg ... ]

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

echotc cap [ arg ... ]

Output the termcap string corresponding to the capability cap, with optional arguments.

enable arg ...

Enable the specified builtin commands, presumably disabled earlier with disable.

eval [ arg ... ]

Read the arguments as input to the shell and execute the resulting command(s) in the current shell process.

exit [ n ]

Exit the shell with the exit code specified by n; if none is specified, use the exit code from the last command executed. An EOF condition will also cause the shell to exit, unless the IGNOREEOF option is set.

export [ name[=value] ... ]

The specified names are marked for automatic export to the environment of subsequently executed commands.

fc [ -e ename ] [ -nlrdDfE ] [ old=new ... ] [ first [ last ] ]
fc -ARWI [ filename ]

Select a range of commands from first to last from the history list. The arguments first and last may be specified as a number or as a string. A negative number is used as an offset to the current history event number. A string specifies the most recent event beginning with the given string. All substitutions old=new, if any, are then performed on the commands. If the -l flag is given, the resulting commands are listed on standard output. Otherwise the editor program ename is invoked on a file containing these history events. If ename is not given, the value of the parameter FCEDIT is used. If ename is "-", no editor is invoked. When editing is complete, the edited command(s) is executed. If first is not specified, it will be set to -1 (the most recent event), or to -16 if the -l flag is given. If last is not specified, it will be set to first, or to -1 if the -l flag is given. The flag -r reverses the order of the commands and the flag -n suppresses command numbers when listing. Also when listing, -d prints timestamps for each command, and -f prints full time-date stamps. Adding the -E flag causes the dates to be printed as ’dd.mm.yyyy’. With the -D flag, fc prints elapsed times.

fc -R reads the history from the given file, fc -W writes the history out to the given file, and fc -A appends the history out to the given file. fc -AI ( -WI ) appends ( writes ) only those events that are new since last incremental append ( write ) to the history file.

fg [ job ... ]
job ...

Bring the specified jobs to the foreground. If no job is specified, use the current job.

functions [ ±tu ] [ name ... ]

Equivalent to typeset -f.

getln name ...

Read the top value from the buffer stack and put it in the shell parameter name. Equivalent to read -zr.

getopts optstring name [ arg ... ]

Checks arg for legal options. If arg is omitted, use the positional parameters. A valid option argument begins with a + or a -. An argument not beginning with a + or a -, or the argument --, ends the options. optstring contains the letters that getopts recognizes. If a letter is followed by a ’:’, that option is expected to have an argument. The options can be separated from the argument by blanks.

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

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

hash name path

Puts name in the command hash table, associating it with the pathname path. Whenever name is used as a command argument, the shell will try to execute the file given by path.

history [ -nr ] [ first [ last ] ]

Same as fc -l.

integer

Same as typeset -i.

jobs [ -lp ] [ job ... ]

Lists information about each given job, or all jobs if job is omitted. The -l flag lists process ids, and the -p flag lists process groups.

kill [ -sig ] job ...
kill -l

Sends either SIGTERM or the specified signal to the given jobs or processes. Signals are given by number or by names (with the prefix "SIG" removed). If the signal being sent is not KILL or CONT, then the job will be sent a CONT signal if it is stopped. The argument job can be the process id of a job not in the job list. In the second form, kill -l, the signal names are listed.

let arg ...

Evaluate each arg as an arithmetic expression. See ARITHMETIC EVALUATION above for a description of arithmetic expressions. The exit status is 0 if the value of the last expression is nonzero, and 1 otherwise.

limit [ -h ] [ resource [ limit ] ] ...
limit -s

Limit the resource consumption of children of the current shell. If limit is not specified, print the current limit placed on resource; otherwise set the limit to the specified value. If the -h flag is given, use hard limits instead of soft limits. If no resource is given, print all limits.

resource is one of:
cputime

Maximum CPU seconds per process.

filesize

Largest single file allowed.

datasize

Maximum data size (including stack) for each process.

stacksize

Maximum stack size for each process.

coredumpsize

Maximum size of a core dump.

resident

Maximum resident set size.

descriptors

Maximum value for a file descriptor.

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

Same as typeset.

popd [ ±n ]

Removes entries from the directory stack. With no arguments, removes the top directory from the stack, and performs a cd to the new top directory. With an argument of the form +n, remove the nth entry counting from the left of the list shown by the dirs command, starting with zero, and change to that directory. With an argument of the form -n, remove the nth entry counting from the right. If the PUSHD_MINUS option is set, the meanings of + and - in this context are swapped.

print [ -RnrslzpNDP ] [ -un ] [ arg ... ]

With no flags or with flag -, the arguments are printed on the standard output as described by echo.

pushd [ arg ]
pushd old new
pushd ±n

Change the current directory, and push the old current directory onto the directory stack. In the first form, change the current directory to arg. If arg is not specified, change to the second directory on the stack (that is, exchange the top two entries), or change to the value of HOME if the PUSHD_TO_HOME option is set or if there is only one entry on the stack. If arg is -, change to the value of OLDPWD, the previous directory. If a directory named arg is not found in the current directory and arg does not contain a slash, search each component of the shell parameter cdpath. If the option CDABLEVARS is set, and a parameter named arg exists whose value begins with a slash, treat its value as the directory. If the option PUSHD_SILENT is not set, the directory stack will be printed after a pushd is performed.

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

The third form of pushd is equivalent to popd.

read [ -rzp ] [ -un ] [ name?prompt ] [ name ... ]

Read one line and break it into fields using the characters in IFS as separators. In raw mode, -r, a \ at the end of a line does not signify line continuation. If the -z flag is set, read from the editor buffer stack. The first field is assigned to the first name, the second field to the second name, etc., with leftover fields assigned to the last name. If name is omitted then REPLY is used. If -un is specified, then input is read from file descriptor n; if -p is specified, then input is read from the coprocess. The exit status is 0 unless end-of-file is encountered. If the first argument contains a ?, the remainder of this word is used as a prompt on standard error when the shell is interactive. The exit status is 0 unless an end-of-file is encountered.

readonly [ name[=value] ] ...

The given names are marked readonly; these names cannot be changed by subsequent assignment.

rehash [ -f ]

Throw out the command hash table and start over. If the -f option is set, rescan the command path immediately, instead of rebuilding the hash table incrementally.

return [ n ]

Causes a shell function or . script to return to the invoking script with the return status specified by n. If n is omitted then the return status is that of the last command executed.

sched [+]hh:mm 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. With no arguments, prints the list of scheduled commands. With the argument -item, removes the given item from the list.

set [ ±options ] [ ±o option name ] ... [ -A name ] [ arg ] ...

Set the options for the shell and/or set the positional parameters, or declare an array. For the meaning of the flags, see OPTIONS above. Flags may be specified by name using the -o option. If the -A flag is specified, name is set to an array containing the given args. Otherwise the positional parameters are set. If no arguments are given, then the names and values of all parameters are printed on the standard output. If the only argument is +, the names of all parameters are printed.

setopt [ ±options ] [ name ... ]

Set the options for the shell. All options specified either with flags or by name are set. If no arguments are supplied, the names of all options currently set are printed. In option names, case is insignificant, and all underscore characters are ignored.

shift [ n ]

The positional parameters from $n+1 ... are renamed $1, where n is an arithmetic expression that defaults to 1.

suspend [ -f ]

Suspend the execution of the shell (send it a SIGTSTP) until it receives a SIGCONT. If the -f option is not given, complain if this is a login shell.

test arg ...
[ arg ... ]

Like the system version of test. Added for compatibility; use conditional expressions instead.

trap [ arg ] [ sig ] ...

arg is a command to be read and executed when the shell receives sig. Each sig can be given as a number or as the name of a signal. If arg is -, then all traps sig are reset to their default values. If arg is the null string, then this signal is ignored by the shell and by the commands it invokes. If sig is ERR then arg will be executed after each command. If sig is 0 or EXIT and the trap statement is executed inside the body of a function, then the command arg is executed after the function completes. If sig is 0 or EXIT and the trap statement is not executed inside the body of a function, then the command arg is executed when the shell terminates. The trap command with no arguments prints a list of commands associated with each signal.

ttyctl -fu

The -f option freezes the tty, and -u unfreezes it. When the tty is frozen, no changes made to the tty settings by external programs will be honored by the shell; the shell will simply reset the settings to their previous values as soon as each command exits. Thus, stty and similar programs have no effect when the tty is frozen.

typeset [ ±LRZfilrtux [n]] [ name[=value] ] ...

Set attributes and values for shell parameters. When invoked inside a function, if name is not already defined, a new parameter is created which will be unset when the function completes. The following attributes are valid:

Using + rather than - causes these flags to be turned off. If no arguments are given but flags are specified, a list of named parameters which have these flags set is printed. Using + instead of - keeps their values from being printed. If no arguments or options are given, the names and attributes of all parameters are printed.
ulimit [ -HSacdfmnt ] [ limit ]

Set or display a resource limit. The value of limit can be a number in the unit specified below or the value unlimited. The H and S flags specify whether the hard limit or the soft limit for the given resource is set.

umask [ mask ]

The umask is set to mask. mask can be either an octal number or a symbolic value as described in chmod(1). If mask is omitted, the current value is printed.

unalias name ...

The alias definition, if any, for each name is removed.

unfunction name ...

The function definition, if any, for each name is removed.

unhash name ...

The entry in the command hash table, if any, for each name is removed.

unlimit [ -h ] resource ...

The resource limit for each resource is set to the hard limit. If the -h flag is given and the shell is running as root, the hard resource limit for each resource is removed.

unset name ...

Each named parameter is unset.

unsetopt [ ±options ] [ name ... ]

Unset the options for the shell. All options specified either with flags or by name are unset.

vared name

The value of the parameter name is loaded into the edit buffer, and the line editor is invoked. When the editor exits, name is set to the string value returned by the editor.

wait [ job ... ]

Wait for the specified jobs or processes. If job is not given then all currently active child processes are waited for. Each job can be either a job specification or the process-id of a job in the job table. The exit status from this command is that of the job waited for.

whence [ -acpv ] name ...

For each name, indicate how it would be interpreted if used as a command name. The -v flag produces a more verbose report. The -p flag does a path search for name even if it is a shell function, alias, or reserved word. The -c flag prints the results in a csh-like format. The -a flag does a search for all occurences of name throughout the command path.

INVOCATION

Commands are first read from /etc/zshenv. Then, if the NO_RCS option is unset, commands are read from $ZDOTDIR/.zshenv. (If ZDOTDIR is unset, HOME is used instead). If the first character of argument zero passed to the shell is -, or if the -l flag is present, then the shell is assumed to be a login shell, and commands are read from /etc/zprofile and then $ZDOTDIR/.zprofile. Then, if the shell is interactive and the NO_RCS option is unset, 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.

If the NO_RCS option is set within /etc/zshenv, then only /etc/zprofile, /etc/zshrc, and /etc/zlogin are read, and the $ZDOTDIR files are skipped. If the -f flag is present, only /etc/zshenv is read, and all other initialization files are skipped.

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. The remaining arguments are assigned to the positional parameters. The following flags are interpreted by the shell when invoked:
-c string

Read commands from string.

SEE ALSO

sh(1), csh(1), tcsh(1), itcsh(1), rc(1), bash(1), ash(1), ksh(1), clam(1), strftime(3).

FILES

$ZDOTDIR/.zshenv
$ZDOTDIR/.zprofile
$ZDOTDIR/.zshrc
$ZDOTDIR/.zlogin
$ZDOTDIR/.zlogout
/tmp/zsh*
/etc/zshenv
/etc/zprofile
/etc/zshrc
/etc/zlogin

AUTHOR

Paul Falstad (pf@ttisms.com)

AVAILABILITY

The latest official release of zsh is available via anonymous ftp from cs.ucsd.edu (132.239.51.3), in the directory pub/zsh. The beta release of zsh 2.4 is available from carlo.phys.uva.nl (145.18.220.25), in the directory pub/bas/zsh. This man page is current to zsh 2.3.1.

UNDOCUMENTED FEATURES

Known only to the recipients of the zsh mailing list, zsh-list@cs.uow.edu.au. If you run into problems, please send your questions and patches to the mailing list. To join the list, send email to zsh-request@cs.uow.edu.au.