path: root/Doc/Zsh/options.yo

texinode(Options)(Shell Builtin Commands)(Parameters)(Top)
chapter(Options)
cindex(options)
startmenu()
menu(Specifying Options)
menu(Description of Options)
menu(Option Aliases)
menu(Single Letter Options)
endmenu()
texinode(Specifying Options)(Description of Options)()(Options)
sect(Specifying Options)
cindex(options, specifying)
Options are primarily referred to by name.
These names are case insensitive and underscores are ignored.
For example, `tt(allexport)' is equivalent to `tt(A__lleXP_ort)'.

The sense of an option name may be inverted by preceding it with
`tt(no)', so `tt(setopt No_Beep)' is equivalent to `tt(unsetopt beep)'.
This inversion can only be done once, so `tt(nonobeep)' is em(not)
a synonym for `tt(beep)'.  Similarly, `tt(tify)' is not a synonym for
`tt(nonotify)' (the inversion of `tt(notify)').

Some options also have one or more single letter names.
There are two sets of single letter options: one used by default,
and another used to emulate bf(sh)/bf(ksh) (used when the
tt(SH_OPTION_LETTERS) option is set).
The single letter options can be used on the shell command line,
or with the tt(set), tt(setopt) and tt(unsetopt)
builtins, as normal Unix options preceded by `tt(-)'.

The sense of the single letter options may be inverted by using
`tt(PLUS())' instead of `tt(-)'.
Some of the single letter option names refer to an option being off,
in which case the inversion of that name refers to the option being on.
For example, `tt(PLUS()n)' is the short name of `tt(exec)', and
`tt(-n)' is the short name of its inversion, `tt(noexec)'.

In strings of single letter options supplied to the shell at startup,
trailing whitespace will be ignored; for example the string `tt(-f    )'
will be treated just as `tt(-f)', but the string `tt(-f i)' is an error.
This is because many systems which implement the `tt(#!)' mechanism for
calling scripts do not strip trailing whitespace.

texinode(Description of Options)(Option Aliases)(Specifying Options)(Options)
sect(Description of Options)
cindex(options, description)
In the following list, options set by default in all emulations are marked
<D>; those set by default only in csh, ksh, sh, or zsh emulations are marked
<C>, <K>, <S>, <Z> as appropriate.  When listing options (by `tt(setopt)',
`tt(unsetopt)', `tt(set -o)' or `tt(set +o)'), those turned on by default
appear in the list prefixed with `tt(no)'.  Hence (unless
tt(KSH_OPTION_PRINT) is set), `tt(setopt)' shows all options whose settings
are changed from the default.

subsect(Changing Directories)
startitem()
pindex(AUTO_CD)
cindex(cd, automatic)
item(tt(AUTO_CD) (tt(-J)))(
If a command is issued that can't be executed as a normal command,
and the command is the name of a directory, perform the tt(cd)
command to that directory.
)
pindex(AUTO_PUSHD)
cindex(cd, behaving like pushd)
cindex(pushd, making cd behave like)
item(tt(AUTO_PUSHD) (tt(-N)))(
Make tt(cd) push the old directory onto the directory stack.
)
pindex(CDABLE_VARS)
cindex(cd, to parameter)
item(tt(CDABLE_VARS) (tt(-T)))(
If the argument to a tt(cd) command (or an implied tt(cd) with the
tt(AUTO_CD) option set) is not a directory, and does not begin with a
slash, try to expand the expression as if it were preceded by a `tt(~)' (see
noderef(Filename Expansion)).
)
pindex(CHASE_DOTS)
cindex(cd, with .. in argument)
item(tt(CHASE_DOTS))(
When changing to a directory containing a path segment `tt(..)' which would
otherwise be treated as canceling the previous segment in the path (in
other words, `tt(foo/..)' would be removed from the path, or if `tt(..)' is
the first part of the path, the last part of tt($PWD) would be deleted),
instead resolve the path to the physical directory.  This option is
overridden by tt(CHASE_LINKS).

For example, suppose tt(/foo/bar) is a link to the directory tt(/alt/rod).
Without this option set, `tt(cd /foo/bar/..)' changes to tt(/foo); with it
set, it changes to tt(/alt).  The same applies if the current directory
is tt(/foo/bar) and `tt(cd ..)' is used.  Note that all other symbolic
links in the path will also be resolved.
)
pindex(CHASE_LINKS)
cindex(links, symbolic)
cindex(symbolic links)
item(tt(CHASE_LINKS) (tt(-w)))(
Resolve symbolic links to their true values when changing directory.
This also has the effect of tt(CHASE_DOTS), i.e. a `tt(..)' path segment
will be treated as referring to the physical parent, even if the preceding
path segment is a symbolic link.
)
pindex(PUSHD_IGNORE_DUPS)
cindex(directory stack, ignoring duplicates)
item(tt(PUSHD_IGNORE_DUPS))(
Don't push multiple copies of the same directory onto the directory stack.
)
pindex(PUSHD_MINUS)
cindex(directory stack, controlling syntax)
item(tt(PUSHD_MINUS))(
Exchanges the meanings of `tt(PLUS())' and `tt(-)'
when used with a number to specify a directory in the stack.
)
pindex(PUSHD_SILENT)
cindex(directory stack, silencing)
item(tt(PUSHD_SILENT) (tt(-E)))(
Do not print the directory stack after tt(pushd) or tt(popd).
)
pindex(PUSHD_TO_HOME)
cindex(pushd, to home)
item(tt(PUSHD_TO_HOME) (tt(-D)))(
Have tt(pushd) with no arguments act like `tt(pushd $HOME)'.
)
enditem()

subsect(Completion)
startitem()
pindex(ALWAYS_LAST_PROMPT)
item(tt(ALWAYS_LAST_PROMPT) <D>)(
If unset, key functions that list completions try to return to the last
prompt if given a numeric argument. If set these functions try to
return to the last prompt if given em(no) numeric argument.
)
pindex(ALWAYS_TO_END)
item(tt(ALWAYS_TO_END))(
If a completion is performed with the cursor within a word, and a
full completion is inserted, the cursor is moved to the end of the
word.  That is, the cursor is moved to the end of the word if either
a single match is inserted or menu completion is performed.
)
pindex(AUTO_LIST)
cindex(completion, listing choices)
item(tt(AUTO_LIST) (tt(-9)) <D>)(
Automatically list choices on an ambiguous completion.
)
pindex(AUTO_MENU)
cindex(completion, menu)
item(tt(AUTO_MENU) <D>)(
Automatically use menu completion after the second consecutive request for
completion, for example by pressing the tab key repeatedly. This option
is overridden by tt(MENU_COMPLETE).
)
pindex(AUTO_NAME_DIRS)
cindex(directories, named)
item(tt(AUTO_NAME_DIRS))(
Any parameter that is set to the absolute name of a directory
immediately becomes a name for that directory, that will be used
by the `tt(%~)'
and related prompt sequences, and will be available when completion
is performed on a word starting with `tt(~)'.
(Otherwise, the parameter must be used in the form `tt(~)var(param)' first.)
)
pindex(AUTO_PARAM_KEYS)
item(tt(AUTO_PARAM_KEYS) <D>)(
If a parameter name was completed and a following character
(normally a space) automatically
inserted, and the next character typed is one
of those that have to come directly after the name (like `tt(})', `tt(:)',
etc.), the automatically added character is deleted, so that the character
typed comes immediately after the parameter name.
Completion in a brace expansion is affected similarly: the added character
is a `tt(,)', which will be removed if `tt(})' is typed next.
)
pindex(AUTO_PARAM_SLASH)
item(tt(AUTO_PARAM_SLASH) <D>)(
If a parameter is completed whose content is the name of a directory,
then add a trailing slash instead of a space.
)
pindex(AUTO_REMOVE_SLASH)
cindex(slash, removing trailing)
item(tt(AUTO_REMOVE_SLASH) <D>)(
When the last character resulting from a completion is a slash and the next
character typed is a word delimiter, a slash, or a character that ends 
a command (such as a semicolon or an ampersand), remove the slash.
)
pindex(BASH_AUTO_LIST)
cindex(completion, listing choices, bash style)
item(tt(BASH_AUTO_LIST))(
On an ambiguous completion, automatically list choices when the
completion function is called twice in succession.  This takes
precedence over tt(AUTO_LIST).  The setting of tt(LIST_AMBIGUOUS) is
respected.  If tt(AUTO_MENU) is set, the menu behaviour will then start
with the third press.  Note that this will not work with
tt(MENU_COMPLETE), since repeated completion calls immediately cycle
through the list in that case.
)
pindex(COMPLETE_ALIASES)
cindex(aliases, completion of)
item(tt(COMPLETE_ALIASES))(
Prevents aliases on the command line from being internally substituted
before completion is attempted.  The effect is to make the alias a
distinct command for completion purposes.
)
pindex(COMPLETE_IN_WORD)
item(tt(COMPLETE_IN_WORD))(
If unset, the cursor is set to the end of the word if completion is
started. Otherwise it stays there and completion is done from both ends.
)
pindex(GLOB_COMPLETE)
item(tt(GLOB_COMPLETE))(
When the current word has a glob pattern, do not insert all the words
resulting from the expansion but generate matches as for completion and
cycle through them like tt(MENU_COMPLETE). The matches are generated as if
a `tt(*)' was added to the end of the word, or inserted at the cursor when
tt(COMPLETE_IN_WORD) is set.  This actually uses pattern matching, not
globbing, so it works not only for files but for any completion, such as
options, user names, etc.

Note that when the pattern matcher is used, matching control (for example,
case-insensitive or anchored matching) cannot be used.  This limitation
only applies when the current word contains a pattern; simply turning
on the tt(GLOB_COMPLETE) option does not have this effect.
)
pindex(HASH_LIST_ALL)
item(tt(HASH_LIST_ALL) <D>)(
Whenever a command completion is attempted, make sure the entire
command path is hashed first.  This makes the first completion slower.
)
pindex(LIST_AMBIGUOUS)
cindex(ambiguous completion)
cindex(completion, ambiguous)
item(tt(LIST_AMBIGUOUS) <D>)(
This option works when tt(AUTO_LIST) or tt(BASH_AUTO_LIST) is also
set.  If there is an unambiguous prefix to insert on the command line,
that is done without a completion list being displayed; in other
words, auto-listing behaviour only takes place when nothing would be
inserted.  In the case of tt(BASH_AUTO_LIST), this means that the list
will be delayed to the third call of the function.
)
pindex(LIST_BEEP)
cindex(beep, ambiguous completion)
cindex(completion, beep on ambiguous)
item(tt(LIST_BEEP) <D>)(
Beep on an ambiguous completion.  More accurately, this forces the
completion widgets to return status 1 on an ambiguous completion, which
causes the shell to beep if the option tt(BEEP) is also set; this may
be modified if completion is called from a user-defined widget.
)
pindex(LIST_PACKED)
cindex(completion, listing)
item(tt(LIST_PACKED))(
Try to make the completion list smaller (occupying less lines) by
printing the matches in columns with different widths.
)
pindex(LIST_ROWS_FIRST)
cindex(completion, listing order)
item(tt(LIST_ROWS_FIRST))(
Lay out the matches in completion lists sorted horizontally, that is,
the second match is to the right of the first one, not under it as
usual.
)
pindex(LIST_TYPES)
cindex(marking file types)
cindex(files, marking type of)
item(tt(LIST_TYPES) (tt(-X)) <D>)(
When listing files that are possible completions, show the
type of each file with a trailing identifying mark.
)
pindex(MENU_COMPLETE)
cindex(completion, menu)
item(tt(MENU_COMPLETE) (tt(-Y)))(
On an ambiguous completion, instead of listing possibilities or beeping,
insert the first match immediately.  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.
tt(reverse-menu-complete) may be used to loop through the list
in the other direction. This option overrides tt(AUTO_MENU).
)
pindex(REC_EXACT)
cindex(completion, exact matches)
item(tt(REC_EXACT) (tt(-S)))(
In completion, recognize exact matches even
if they are ambiguous.
)
enditem()

subsect(Expansion and Globbing)
startitem()
pindex(BAD_PATTERN)
cindex(globbing, bad pattern)
cindex(filename generation, bad pattern)
item(tt(BAD_PATTERN) (tt(PLUS()2)) <C> <Z>)(
If a pattern for filename generation is badly formed, print an error message.
(If this option is unset, the pattern will be left unchanged.)
)
pindex(BARE_GLOB_QUAL)
cindex(globbing qualifiers, enable)
cindex(enable globbing qualifiers)
item(tt(BARE_GLOB_QUAL) <Z>)(
In a glob pattern, treat a trailing set of parentheses as a qualifier
list, if it contains no `tt(|)', `tt(LPAR())' or (if special) `tt(~)'
characters.  See noderef(Filename Generation).
)
pindex(BRACE_CCL)
cindex(brace expansion, extending)
cindex(expansion, brace, extending)
item(tt(BRACE_CCL))(
Expand expressions in braces which would not otherwise undergo brace
expansion to a lexically ordered list of all the characters.  See
noderef(Brace Expansion).
)
pindex(CASE_GLOB)
cindex(case-insensitive globbing, option)
item(tt(CASE_GLOB) <D>)(
Make globbing (filename generation) sensitive to case.  Note that other
uses of patterns are always sensitive to case.  If the option is unset,
the presence of any character which is special to filename generation
will cause case-insensitive matching.  For example, tt(cvs+LPAR()/+RPAR())
can match the directory tt(CVS) owing to the presence of the globbing flag
(unless the option tt(BARE_GLOB_QUAL) is unset).
)
pindex(CASE_MATCH)
cindex(case-insensitive regular expression matches, option)
cindex(regular expressions, case-insensitive matching, option)
item(tt(CASE_MATCH) <D>)(
Make regular expressions using the tt(zsh/regex) module (including
matches with tt(=~)) sensitive to case.
)
pindex(CSH_NULL_GLOB)
cindex(csh, null globbing style)
cindex(null globbing style, csh)
cindex(globbing, null, style, csh)
item(tt(CSH_NULL_GLOB) <C>)(
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 tt(NOMATCH).
)
pindex(EQUALS)
cindex(filename expansion, =)
item(tt(EQUALS) <Z>)(
Perform tt(=) filename expansion.
(See noderef(Filename Expansion).)
)
pindex(EXTENDED_GLOB)
cindex(globbing, extended)
item(tt(EXTENDED_GLOB))(
Treat the `tt(#)', `tt(~)' and `tt(^)' characters as part of patterns
for filename generation, etc.  (An initial unquoted `tt(~)'
always produces named directory expansion.)
)
pindex(GLOB)
cindex(globbing, enabling)
cindex(enabling globbing)
item(tt(GLOB) (tt(PLUS()F), ksh: tt(PLUS()f)) <D>)(
Perform filename generation (globbing).
(See noderef(Filename Generation).)
)
pindex(GLOB_ASSIGN)
item(tt(GLOB_ASSIGN) <C>)(
If this option is set, filename generation (globbing) is
performed on the right hand side of scalar parameter assignments of
the form `var(name)tt(=)var(pattern) (e.g. `tt(foo=*)').
If the result has more than one word the parameter will become an array
with those words as arguments. This option is provided for backwards
compatibility only: globbing is always performed on the right hand side
of array assignments of the form `var(name)tt(=LPAR())var(value)tt(RPAR())'
(e.g. `tt(foo=(*))') and this form is recommended for clarity;
with this option set, it is not possible to predict whether the result
will be an array or a scalar.
)
pindex(GLOB_DOTS)
cindex(globbing, of . files)
item(tt(GLOB_DOTS) (tt(-4)))(
Do not require a leading `tt(.)' in a filename to be matched explicitly.
)
pindex(GLOB_SUBST)
item(tt(GLOB_SUBST) <C> <K> <S>)(
Treat any characters resulting from parameter expansion as being
eligible for file expansion and filename generation, and any
characters resulting from command substitution as being eligible for
filename generation.  Braces (and commas in between) do not become eligible
for expansion.
)
pindex(HIST_SUBST_PATTERN)
item(tt(HIST_SUBST_PATTERN))(
Substitutions using the tt(:s) and tt(:&) history modifiers are performed
with pattern matching instead of string matching.  This occurs wherever
history modifiers are valid, including glob qualifiers and parameters.
See
ifzman(the section Modifiers in zmanref(zshexp))\
ifnzman(noderef(Modifiers)).
)
pindex(IGNORE_BRACES)
cindex(disabling brace expansion)
cindex(brace expansion, disabling)
cindex(expansion, brace, disabling)
item(tt(IGNORE_BRACES) (tt(-I)) <S>)(
Do not perform brace expansion.
)
pindex(KSH_GLOB)
item(tt(KSH_GLOB) <K>)(
In pattern matching, the interpretation of parentheses is affected by
a preceding `tt(@)', `tt(*)', `tt(+)', `tt(?)' or `tt(!)'.
See noderef(Filename Generation).
)
pindex(MAGIC_EQUAL_SUBST)
item(tt(MAGIC_EQUAL_SUBST))(
All unquoted arguments of the form `var(anything)tt(=)var(expression)'
appearing after the command name have filename expansion (that is,
where var(expression) has a leading `tt(~)' or `tt(=)') performed on
var(expression) as if it were a parameter assignment.  The argument is
not otherwise treated specially; it is passed to the command as a single
argument, and not used as an actual parameter assignment.  For example, in
tt(echo foo=~/bar:~/rod), both occurrences of tt(~) would be replaced.
Note that this happens anyway with tt(typeset) and similar statements.

This option respects the setting of the tt(KSH_TYPESET) option.  In other
words, if both options are in effect, arguments looking like
assignments will not undergo word splitting.
)
pindex(MARK_DIRS)
cindex(directories, marking)
cindex(marking directories)
item(tt(MARK_DIRS) (tt(-8), ksh: tt(-X)))(
Append a trailing `tt(/)' to all directory
names resulting from filename generation (globbing).
)
pindex(MULTIBYTE)
cindex(characters, multibyte, in expansion and globbing)
cindex(multibyte characters, in expansion and globbing)
item(tt(MULTIBYTE) <C> <K> <Z>)(
Respect multibyte characters when found in strings.
When this option is set, strings are examined using the
system library to determine how many bytes form a character, depending
on the current locale.  This affects the way characters are counted in
pattern matching, parameter values and various delimiters.

The option is on by default if the shell was compiled with
tt(MULTIBYTE_SUPPORT) except in tt(sh) emulation; otherwise it is off by
default and has no effect if turned on.  The mode is off in tt(sh)
emulation for compatibility but for interactive use may need to be
turned on if the terminal interprets multibyte characters.

If the option is off a single byte is always treated as a single
character.  This setting is designed purely for examining strings
known to contain raw bytes or other values that may not be characters
in the current locale.  It is not necessary to unset the option merely
because the character set for the current locale does not contain multibyte
characters.

The option does not affect the shell's editor,  which always uses the
locale to determine multibyte characters.  This is because
the character set displayed by the terminal emulator is independent of
shell settings.
)
pindex(NOMATCH)
cindex(globbing, no matches)
item(tt(NOMATCH) (tt(PLUS()3)) <C> <Z>)(
If a pattern for filename generation has no matches,
print an error, instead of
leaving it unchanged in the argument list.
This also applies to file expansion
of an initial `tt(~)' or `tt(=)'.
)
pindex(NULL_GLOB)
cindex(globbing, no matches)
item(tt(NULL_GLOB) (tt(-G)))(
If a pattern for filename generation has no matches,
delete the pattern from the argument list instead
of reporting an error.  Overrides tt(NOMATCH).
)
pindex(NUMERIC_GLOB_SORT)
cindex(globbing, sorting numerically)
item(tt(NUMERIC_GLOB_SORT))(
If numeric filenames are matched by a filename generation pattern,
sort the filenames numerically rather than lexicographically.
)
pindex(RC_EXPAND_PARAM)
cindex(rc, parameter expansion style)
cindex(parameter expansion style, rc)
item(tt(RC_EXPAND_PARAM) (tt(-P)))(
Array expansions of the form
`var(foo)tt(${)var(xx)tt(})var(bar)', where the parameter
var(xx) is set to tt(LPAR())var(a b c)tt(RPAR()), are substituted with
`var(fooabar foobbar foocbar)' instead of the default
`var(fooa b cbar)'.
)
pindex(REMATCH_PCRE)
cindex(regexp, PCRE)
cindex(PCRE, regexp)
item(tt(REMATCH_PCRE) <Z>)(
If set, regular expression matching with the tt(=~) operator will use
Perl-Compatible Regular Expressions from the PCRE library, if available.
If not set, regular expressions will use the extended regexp syntax
provided by the system libraries.
)
pindex(SH_GLOB)
cindex(sh, globbing style)
cindex(globbing style, sh)
item(tt(SH_GLOB) <K> <S>)(
Disables the special meaning of `tt(LPAR())', `tt(|)', `tt(RPAR())'
and 'tt(<)' for globbing the result of parameter and command substitutions,
and in some other places where
the shell accepts patterns.  This option is set by default if zsh is
invoked as tt(sh) or tt(ksh).
)
pindex(UNSET)
cindex(parameters, substituting unset)
cindex(unset parameters, substituting)
item(tt(UNSET) (tt(PLUS()u), ksh: tt(PLUS()u)) <K> <S> <Z>)(
Treat unset parameters as if they were empty when substituting.
Otherwise they are treated as an error.
)
pindex(WARN_CREATE_GLOBAL)
cindex(parameters, warning when created globally)
item(tt(WARN_CREATE_GLOBAL))(
Print a warning message when a global parameter is created in a function
by an assignment.  This often indicates that a parameter has not been
declared local when it should have been.  Parameters explicitly declared
global from within a function using tt(typeset -g) do not cause a warning.
Note that there is no warning when a local parameter is assigned to in
a nested function, which may also indicate an error.
)
enditem()

subsect(History)
startitem()
pindex(APPEND_HISTORY)
cindex(history, appending to a file)
item(tt(APPEND_HISTORY) <D>)(
If this is set, zsh sessions will append their history list to
the history file, rather than replace it. Thus, multiple parallel
zsh sessions will all have the new entries from their history lists
added to the history file, in the order that they exit.
The file will still be periodically re-written to trim it when the
number of lines grows 20% beyond the value specified by
tt($SAVEHIST) (see also the HIST_SAVE_BY_COPY option).
)
pindex(BANG_HIST)
cindex(history, enable substitution)
cindex(enable history substitution)
item(tt(BANG_HIST) (tt(PLUS()K)) <C> <Z>)(
Perform textual history expansion, bf(csh)-style,
treating the character `tt(!)' specially.
)
pindex(EXTENDED_HISTORY)
cindex(history, timestamping)
item(tt(EXTENDED_HISTORY) <C>)(
Save each command's beginning timestamp (in seconds since the epoch)
and the duration (in seconds) to the history file.  The format of
this prefixed data is:

`tt(:)var(<beginning time>)tt(:)var(<elapsed seconds>)tt(:)var(<command>)'.
)
pindex(HIST_ALLOW_CLOBBER)
item(tt(HIST_ALLOW_CLOBBER))(
Add `tt(|)' to output redirections in the history.  This allows history
references to clobber files even when tt(CLOBBER) is unset.
)
pindex(HIST_BEEP)
cindex(history beeping)
cindex(beep, history)
item(tt(HIST_BEEP) <D>)(
Beep when an attempt is made to access a history entry which
isn't there.
)
pindex(HIST_EXPIRE_DUPS_FIRST)
cindex(history, expiring duplicates)
item(tt(HIST_EXPIRE_DUPS_FIRST))(
If the internal history needs to be trimmed to add the current command line,
setting this option will cause the oldest history event that has a duplicate
to be lost before losing a unique event from the list.
You should be sure to set the value of tt(HISTSIZE) to a larger number
than tt(SAVEHIST) in order to give you some room for the duplicated
events, otherwise this option will behave just like
tt(HIST_IGNORE_ALL_DUPS) once the history fills up with unique events.
)
pindex(HIST_FCNTL_LOCK)
item(tt(HIST_FCNTL_LOCK))(
When writing out the history file, by default zsh uses ad-hoc file locking
to avoid known problems with locking on some operating systems.  With this
option locking is done by means of the system's tt(fcntl) call, where
this method is available.  On recent operating systems this may
provide better performance, in particular avoiding history corruption when
files are stored on NFS.
)
pindex(HIST_FIND_NO_DUPS)
cindex(history, ignoring duplicates in search)
item(tt(HIST_FIND_NO_DUPS))(
When searching for history entries in the line editor, do not display
duplicates of a line previously found, even if the duplicates are not
contiguous.
)
pindex(HIST_IGNORE_ALL_DUPS)
cindex(history, ignoring all duplicates)
item(tt(HIST_IGNORE_ALL_DUPS))(
If a new command line being added to the history list duplicates an
older one, the older command is removed from the list (even if it is
not the previous event).
)
pindex(HIST_IGNORE_DUPS)
cindex(history, ignoring duplicates)
item(tt(HIST_IGNORE_DUPS) (tt(-h)))(
Do not enter command lines into the history list
if they are duplicates of the previous event.
)
pindex(HIST_IGNORE_SPACE)
cindex(history, ignoring spaces)
item(tt(HIST_IGNORE_SPACE) (tt(-g)))(
Remove command lines from the history list when the first character on
the line is a space, or when one of the expanded aliases contains a
leading space.
Note that the command lingers in the internal history until the next
command is entered before it vanishes, allowing you to briefly reuse
or edit the line.  If you want to make it vanish right away without
entering another command, type a space and press return.
)
pindex(HIST_NO_FUNCTIONS)
item(tt(HIST_NO_FUNCTIONS))(
Remove function definitions from the history list.
Note that the function lingers in the internal history until the next
command is entered before it vanishes, allowing you to briefly reuse
or edit the definition.
)
pindex(HIST_NO_STORE)
item(tt(HIST_NO_STORE))(
Remove the tt(history) (tt(fc -l)) command from the history list
when invoked.
Note that the command lingers in the internal history until the next
command is entered before it vanishes, allowing you to briefly reuse
or edit the line.
)
pindex(HIST_REDUCE_BLANKS)
item(tt(HIST_REDUCE_BLANKS))(
Remove superfluous blanks from each command line
being added to the history list.
)
pindex(HIST_SAVE_BY_COPY)
item(tt(HIST_SAVE_BY_COPY) <D>)(
When the history file is re-written, we normally write out a copy of
the file named $HISTFILE.new and then rename it over the old one.
However, if this option is unset, we instead truncate the old
history file and write out the new version in-place.  If one of the
history-appending options is enabled, this option only has an effect
when the enlarged history file needs to be re-written to trim it
down to size.  Disable this only if you have special needs, as doing
so makes it possible to lose history entries if zsh gets interrupted
during the save.

When writing out a copy of the history file, zsh preserves the old
file's permissions and group information, but will refuse to write
out a new file if it would change the history file's owner.
)
pindex(HIST_SAVE_NO_DUPS)
item(tt(HIST_SAVE_NO_DUPS))(
When writing out the history file, older commands that duplicate
newer ones are omitted.
)
pindex(HIST_VERIFY)
cindex(history, verifying substitution)
item(tt(HIST_VERIFY))(
Whenever the user enters a line with history expansion,
don't execute the line directly; instead, perform
history expansion and reload the line into the editing buffer.
)
pindex(INC_APPEND_HISTORY)
cindex(history, incremental appending to a file)
item(tt(INC_APPEND_HISTORY))(
This options works like tt(APPEND_HISTORY) except that new history lines
are added to the tt($HISTFILE) incrementally (as soon as they are
entered), rather than waiting until the shell exits.
The file will still be periodically re-written to trim it when the
number of lines grows 20% beyond the value specified by
tt($SAVEHIST) (see also the HIST_SAVE_BY_COPY option).
)
pindex(SHARE_HISTORY)
cindex(share history)
cindex(history, sharing)
item(tt(SHARE_HISTORY) <K>)(

This option both imports new commands from the history file, and also
causes your typed commands to be appended to the history file (the
latter is like specifying tt(INC_APPEND_HISTORY)).
The history lines are also output with timestamps ala
tt(EXTENDED_HISTORY) (which makes it easier to find the spot where
we left off reading the file after it gets re-written).

By default, history movement commands visit the imported lines as
well as the local lines, but you can toggle this on and off with the
set-local-history zle binding.  It is also possible to create a zle
widget that will make some commands ignore imported commands, and
some include them.

If you find that you want more control over when commands
get imported, you may wish to turn tt(SHARE_HISTORY) off,
tt(INC_APPEND_HISTORY) on, and then manually import
commands whenever you need them using `tt(fc -RI)'.
)
enditem()

subsect(Initialisation)
startitem()
pindex(ALL_EXPORT)
cindex(export, automatic)
item(tt(ALL_EXPORT) (tt(-a), ksh: tt(-a)))(
All parameters subsequently defined are automatically exported.
)
pindex(GLOBAL_EXPORT)
cindex(environment, and local parameters)
item(tt(GLOBAL_EXPORT) (tt(<Z>)))(
If this option is set, passing the tt(-x) flag to the builtins tt(declare),
tt(float), tt(integer), tt(readonly) and tt(typeset) (but not tt(local))
will also set the tt(-g) flag;  hence parameters exported to
the environment will not be made local to the enclosing function, unless
they were already or the flag tt(+g) is given explicitly.  If the option is
unset, exported parameters will be made local in just the same way as any
other parameter.

This option is set by default for backward compatibility; it is not
recommended that its behaviour be relied upon.  Note that the builtin
tt(export) always sets both the tt(-x) and tt(-g) flags, and hence its
effect extends beyond the scope of the enclosing function; this is the
most portable way to achieve this behaviour.
)
cindex(exporting, and local parameters)
pindex(GLOBAL_RCS)
cindex(startup files, global, inhibiting)
cindex(files, global startup, inhibiting)
item(tt(GLOBAL_RCS) (tt(-d)) <D>)(
If this option is unset, the startup files tt(/etc/zprofile),
tt(/etc/zshrc), tt(/etc/zlogin) and tt(/etc/zlogout) will not be run.  It
can be disabled and re-enabled at any time, including inside local startup
files (tt(.zshrc), etc.).
)
pindex(RCS)
cindex(startup files, sourcing)
item(tt(RCS) (tt(PLUS()f)) <D>)(
After tt(/etc/zshenv) is sourced on startup, source the
tt(.zshenv), tt(/etc/zprofile), tt(.zprofile),
tt(/etc/zshrc), tt(.zshrc), tt(/etc/zlogin), tt(.zlogin), and tt(.zlogout)
files, as described in noderef(Files).
If this option is unset, the tt(/etc/zshenv) file is still sourced, but any
of the others will not be; it can be set at any time to prevent the
remaining startup files after the currently executing one from
being sourced.
)
enditem()

subsect(Input/Output)
startitem()
pindex(ALIASES)
cindex(aliases, expansion)
item(tt(ALIASES) <D>)(
Expand aliases.
)
pindex(CLOBBER)
cindex(clobbering, of files)
cindex(file clobbering, allowing)
item(tt(CLOBBER) (tt(PLUS()C), ksh: tt(PLUS()C)) <D>)(
Allows `tt(>)' redirection to truncate existing files,
and `tt(>>)' to create files.
Otherwise `tt(>!)' or `tt(>|)' must be used to truncate a file,
and `tt(>>!)' or `tt(>>|)' to create a file.
)
pindex(CORRECT)
cindex(correction, spelling)
cindex(spelling correction)
item(tt(CORRECT) (tt(-0)))(
Try to correct the spelling of commands.
Note that, when the tt(HASH_LIST_ALL) option is not set or when some
directories in the path are not readable, this may falsely report spelling
errors the first time some commands are used.
)
pindex(CORRECT_ALL)
item(tt(CORRECT_ALL) (tt(-O)))(
Try to correct the spelling of all arguments in a line.
)
pindex(DVORAK)
item(tt(DVORAK))(
Use the Dvorak keyboard instead of the standard qwerty keyboard as a basis
for examining spelling mistakes for the tt(CORRECT) and tt(CORRECT_ALL)
options and the tt(spell-word) editor command.
)
pindex(FLOW_CONTROL)
cindex(flow control)
item(tt(FLOW_CONTROL) <D>)(
If this option is unset,
output flow control via start/stop characters (usually assigned to
^S/^Q) is disabled in the shell's editor.
)
pindex(IGNORE_EOF)
cindex(EOF, ignoring)
item(tt(IGNORE_EOF) (tt(-7)))(
Do not exit on end-of-file.  Require the use
of tt(exit) or tt(logout) instead.
However, ten consecutive EOFs will cause the shell to exit anyway,
to avoid the shell hanging if its tty goes away.

Also, if this option is set and the Zsh Line Editor is used, widgets
implemented by shell functions can be bound to EOF (normally
Control-D) without printing the normal warning message.  This works
only for normal widgets, not for completion widgets.
)
pindex(INTERACTIVE_COMMENTS)
cindex(comments, in interactive shells)
item(tt(INTERACTIVE_COMMENTS) (tt(-k)) <K> <S>)(
Allow comments even in interactive shells.
)
pindex(HASH_CMDS)
cindex(hashing, of commands)
cindex(command hashing)
item(tt(HASH_CMDS) <D>)(
Note the location of each command the first time it is executed.
Subsequent invocations of the same command will use the
saved location, avoiding a path search.
If this option is unset, no path hashing is done at all.
However, when tt(CORRECT) is set, commands whose names do not appear in
the functions or aliases hash tables are hashed in order to avoid
reporting them as spelling errors.
)
pindex(HASH_DIRS)
cindex(hashing, of directories)
cindex(directories, hashing)
item(tt(HASH_DIRS) <D>)(
Whenever a command name is hashed, hash the directory containing it,
as well as all directories that occur earlier in the path.
Has no effect if neither tt(HASH_CMDS) nor tt(CORRECT) is set.
)
pindex(MAIL_WARNING)
cindex(mail, warning of reading)
item(tt(MAIL_WARNING) (tt(-U)))(
Print a warning message if a mail file has been
accessed since the shell last checked.
)
pindex(PATH_DIRS)
cindex(path search, extended)
item(tt(PATH_DIRS) (tt(-Q)))(
Perform a path search even on command names with slashes in them.
Thus if `tt(/usr/local/bin)' is in the user's path, and he or she types
`tt(X11/xinit)', the command `tt(/usr/local/bin/X11/xinit)' will be executed
(assuming it exists).
Commands explicitly beginning with `tt(/)', `tt(./)' or `tt(../)'
are not subject to the path search.
This also applies to the tt(.) builtin.

Note that subdirectories of the current directory are always searched for
executables specified in this form.  This takes place before any search
indicated by this option, and regardless of whether `tt(.)' or the current
directory appear in the command search path.
)
pindex(PRINT_EIGHT_BIT)
cindex(eight bit characters, printing)
item(tt(PRINT_EIGHT_BIT))(
Print eight bit characters literally in completion lists, etc.
This option is not necessary if your system correctly returns the
printability of eight bit characters (see manref(ctype)(3)).
)
pindex(PRINT_EXIT_VALUE)
cindex(exit status, printing)
item(tt(PRINT_EXIT_VALUE) (tt(-1)))(
Print the exit value of programs with non-zero exit status.
)
pindex(RC_QUOTES)
cindex(rc, quoting style)
cindex(quoting style, rc)
item(tt(RC_QUOTES))(
Allow the character sequence `tt('')' to signify a single quote
within singly quoted strings.  Note this does not apply in quoted strings
using the format tt($')var(...)tt('), where a backslashed single quote can
be used.
)
pindex(RM_STAR_SILENT)
cindex(rm *, querying before)
cindex(querying before rm *)
item(tt(RM_STAR_SILENT) (tt(-H)) <K> <S>)(
Do not query the user before executing `tt(rm *)' or `tt(rm path/*)'.
)
pindex(RM_STAR_WAIT)
cindex(rm *, waiting before)
cindex(waiting before rm *)
item(tt(RM_STAR_WAIT))(
If querying the user before executing `tt(rm *)' or `tt(rm path/*)',
first wait ten seconds and ignore anything typed in that time.
This avoids the problem of reflexively answering `yes' to the query
when one didn't really mean it.  The wait and query can always be
avoided by expanding the `tt(*)' in ZLE (with tab).
)
pindex(SHORT_LOOPS)
item(tt(SHORT_LOOPS) <C> <Z>)(
Allow the short forms of tt(for), tt(repeat), tt(select),
tt(if), and tt(function) constructs.
)
pindex(SUN_KEYBOARD_HACK)
cindex(sun keyboard, annoying)
cindex(annoying keyboard, sun)
item(tt(SUN_KEYBOARD_HACK) (tt(-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.
)
enditem()

subsect(Job Control)
startitem()
pindex(AUTO_CONTINUE)
cindex(jobs, continuing automatically)
cindex(continuing jobs automatically)
item(tt(AUTO_CONTINUE))(
With this option set, stopped jobs that are removed from the job table
with the tt(disown) builtin command are automatically sent a tt(CONT)
signal to make them running.
)
pindex(AUTO_RESUME)
cindex(jobs, resuming automatically)
cindex(resuming jobs automatically)
item(tt(AUTO_RESUME) (tt(-W)))(
Treat single word simple commands without redirection
as candidates for resumption of an existing job.
)
pindex(BG_NICE)
cindex(jobs, background priority)
cindex(background jobs, priority of)
cindex(priority of background jobs)
item(tt(BG_NICE) (tt(-6)) <C> <Z>)(
Run all background jobs at a lower priority.  This option
is set by default.
)
pindex(CHECK_JOBS)
cindex(exiting, checking jobs when)
cindex(logging out, checking jobs when)
item(tt(CHECK_JOBS) <Z>)(
Report the status of background and suspended jobs before exiting a shell
with job control; a second attempt to exit the shell will succeed.
tt(NO_CHECK_JOBS) is best used only in combination with tt(NO_HUP), else
such jobs will be killed automatically.

The check is omitted if the commands run from the previous command line
included a `tt(jobs)' command, since it is assumed the user is aware that
there are background or suspended jobs.  A `tt(jobs)' command run from one
of the hook functions defined in
ifnzman(the section Special Functions in noderef(Functions))\
ifzman(the section SPECIAL FUNCTIONS in zmanref(zshmisc))
is not counted for this purpose.
)
pindex(HUP)
cindex(jobs, HUP)
item(tt(HUP) <Z>)(
Send the tt(HUP) signal to running jobs when the
shell exits.
)
pindex(LONG_LIST_JOBS)
cindex(jobs, list format)
item(tt(LONG_LIST_JOBS) (tt(-R)))(
List jobs in the long format by default.
)
pindex(MONITOR)
cindex(job control, allowing)
item(tt(MONITOR) (tt(-m), ksh: tt(-m)))(
Allow job control.  Set by default in interactive shells.
)
pindex(NOTIFY)
cindex(background jobs, notification)
cindex(notification of background jobs)
item(tt(NOTIFY) (tt(-5), ksh: tt(-b)) <Z>)(
Report the status of background jobs immediately, rather than
waiting until just before printing a prompt.
)
enditem()

subsect(Prompting)
startitem()
pindex(PROMPT_BANG)
cindex(prompt, ! expansion)
item(tt(PROMPT_BANG) <K>)(
If set, `tt(!)' is treated specially in prompt expansion.
See noderef(Prompt Expansion).
)
pindex(PROMPT_CR)
cindex(prompt, with CR)
item(tt(PROMPT_CR) (tt(PLUS()V)) <D>)(
Print a carriage return just before printing
a prompt in the line editor.  This is on by default as multi-line editing
is only possible if the editor knows where the start of the line appears.
)
pindex(PROMPT_SP)
cindex(prompt, save partial lines)
item(tt(PROMPT_SP) <D>)(
Attempt to preserve a partial line (i.e. a line that did not end with a
newline) that would otherwise be covered up by the command prompt due to
the PROMPT_CR option.  This works by outputting some cursor-control
characters, including a series of spaces, that should make the terminal
wrap to the next line when a partial line is present (note that this is
only successful if your terminal has automatic margins, which is typical).

When a partial line is preserved, you will see an inverse+bold character at
the end of the partial line:  a "%" for a normal user or a "#" for root.

NOTE: if the PROMPT_CR option is not set, enabling this option will have no
effect.  This option is on by default.
)
pindex(PROMPT_PERCENT)
cindex(prompt, % expansion)
item(tt(PROMPT_PERCENT) <C> <Z>)(
If set, `tt(%)' is treated specially in prompt expansion.
See noderef(Prompt Expansion).
)
pindex(PROMPT_SUBST)
cindex(prompt, parameter expansion)
item(tt(PROMPT_SUBST) <K>)(
If set, em(parameter expansion), em(command substitution) and
em(arithmetic expansion) are performed in prompts.  Substitutions
within prompts do not affect the command status.
)
pindex(TRANSIENT_RPROMPT)
item(tt(TRANSIENT_RPROMPT))(
Remove any right prompt from display when accepting a command
line.  This may be useful with terminals with other cut/paste methods.
)
enditem()

subsect(Scripts and Functions)
startitem()
pindex(C_BASES)
cindex(bases, output in C format)
cindex(hexadecimal, output in C format)
cindex(octal, output in C format)
item(tt(C_BASES))(
Output hexadecimal numbers in the standard C format, for example `tt(0xFF)'
instead of the usual `tt(16#FF)'.  If the option tt(OCTAL_ZEROES) is also
set (it is not by default), octal numbers will be treated similarly and
hence appear as `tt(077)' instead of `tt(8#77)'.  This option has no effect
on the choice of the output base, nor on the output of bases other than
hexadecimal and octal.  Note that these formats will be understood on input
irrespective of the setting of tt(C_BASES).
)
pindex(DEBUG_BEFORE_CMD)
cindex(traps, DEBUG, before or after command)
cindex(DEBUG trap, before or after command)
item(tt(DEBUG_BEFORE_CMD))(
Run the tt(DEBUG) trap before each command; otherwise it is run after
each command.  Setting this option mimics the behaviour of ksh 93; with
the option unset the behaviour is that of ksh 88.
)
pindex(ERR_EXIT)
cindex(exit status, trapping)
item(tt(ERR_EXIT) (tt(-e), ksh: tt(-e)))(
If a command has a non-zero exit status, execute the tt(ZERR)
trap, if set, and exit.  This is disabled while running initialization
scripts.
)
pindex(ERR_RETURN)
cindex(function return, on error)
cindex(return from function, on error)
item(tt(ERR_RETURN))(
If a command has a non-zero exit status, return immediately from the
enclosing function.  The logic is identical to that for tt(ERR_EXIT),
except that an implicit tt(return) statement is executed instead of an
tt(exit).  This will trigger an exit at the outermost level of a
non-interactive script.
)
pindex(EVAL_LINENO)
cindex(line number, in evaluated expression)
item(tt(EVAL_LINENO) <Z>)(
If set, line numbers of expressions evaluated using the builtin tt(eval)
are tracked separately of the enclosing environment.  This applies both
to the parameter tt(LINENO) and the line number output by the prompt
escape tt(%i).  If the option is set, the prompt escape tt(%N) will output
the string `tt((eval))' instead of the script or function name as an
indication.   (The two prompt escapes are typically used in the parameter
tt(PS4) to be output when the option tt(XTRACE) is set.)  If
tt(EVAL_LINENO) is unset, the line number of the surrounding script or
function is retained during the evaluation.
)
pindex(EXEC)
cindex(command execution, enabling)
item(tt(EXEC) (tt(PLUS()n), ksh: tt(PLUS()n)) <D>)(
Do execute commands.  Without this option, commands are
read and checked for syntax errors, but not executed.
This option cannot be turned off in an interactive shell,
except when `tt(-n)' is supplied to the shell at startup.
)
pindex(FUNCTION_ARGZERO)
cindex($0, setting)
item(tt(FUNCTION_ARGZERO) <C> <Z>)(
When executing a shell function or sourcing a script, set tt($0)
temporarily to the name of the function/script.
)
pindex(LOCAL_OPTIONS)
item(tt(LOCAL_OPTIONS) <K>)(
If this option is set at the point of return from a shell function,
all the options (including this one) which were in force upon entry to
the function are restored.  Otherwise, only this option and the
tt(XTRACE) and tt(PRINT_EXIT_VALUE) options are restored.  Hence
if this is explicitly unset by a shell function the other options in
force at the point of return will remain so.
A shell function can also guarantee itself a known shell configuration
with a formulation like `tt(emulate -L zsh)'; the tt(-L) activates
tt(LOCAL_OPTIONS).
)
pindex(LOCAL_TRAPS)
item(tt(LOCAL_TRAPS) <K>)(
If this option is set when a signal trap is set inside a function, then the
previous status of the trap for that signal will be restored when the
function exits.  Note that this option must be set em(prior) to altering the
trap behaviour in a function; unlike tt(LOCAL_OPTIONS), the value on exit
from the function is irrelevant.  However, it does not need to be set
before any global trap for that to be correctly restored by a function.
For example,

example(unsetopt localtraps
trap - INT
fn+LPAR()RPAR() { setopt localtraps; trap '' INT; sleep 3; })

will restore normally handling of tt(SIGINT) after the function exits.
)
pindex(MULTIOS)
item(tt(MULTIOS) <Z>)(
Perform implicit bf(tee)s or bf(cat)s when multiple
redirections are attempted (see noderef(Redirection)).
)
pindex(OCTAL_ZEROES)
cindex(octal, arithmetic expressions)
item(tt(OCTAL_ZEROES) <S>)(
Interpret any integer constant beginning with a 0 as octal, per IEEE Std
1003.2-1992 (ISO 9945-2:1993).  This is not enabled by default as it
causes problems with parsing of, for example, date and time strings with
leading zeroes.

Sequences of digits indicating a numeric base such as the `tt(08)'
component in `tt(08#77)' are always interpreted as decimal, regardless
of leading zeroes.
)
pindex(TYPESET_SILENT)
item(tt(TYPESET_SILENT))(
If this is unset, executing any of the `tt(typeset)' family of
commands with no options and a list of parameters that have no values
to be assigned but already exist will display the value of the parameter.
If the option is set, they will only be shown when parameters are selected
with the `tt(-m)' option.  The option `tt(-p)' is available whether or not
the option is set.
)
pindex(VERBOSE)
cindex(tracing, of input lines)
cindex(input, tracing)
item(tt(VERBOSE) (tt(-v), ksh: tt(-v)))(
Print shell input lines as they are read.
)
pindex(XTRACE)
cindex(tracing, of commands)
cindex(commands, tracing)
item(tt(XTRACE) (tt(-x), ksh: tt(-x)))(
Print commands and their arguments as they are executed.
)
enditem()

subsect(Shell Emulation)
startitem()
pindex(BASH_REMATCH)
cindex(bash, BASH_REMATCH variable)
cindex(regexp, bash BASH_REMATCH variable)
item(tt(BASH_REMATCH))(
When set, matches performed with the tt(=~) operator will set the
tt(BASH_REMATCH) array variable, instead of the default tt(MATCH) and
tt(match) variables.  The first element of the tt(BASH_REMATCH) array
will contain the entire matched text and subsequent elements will contain
extracted substrings.  This option makes more sense when tt(KSH_ARRAYS) is
also set, so that the entire matched portion is stored at index 0 and the
first substring is at index 1.  Without this option, the tt(MATCH) variable
contains the entire matched text and the tt(match) array variable contains
substrings.
)
pindex(BSD_ECHO)
cindex(echo, BSD compatible)
item(tt(BSD_ECHO) <S>)(
Make the tt(echo) builtin compatible with the BSD manref(echo)(1) command.
This disables backslashed escape sequences in echo strings unless the
tt(-e) option is specified.
)
pindex(CSH_JUNKIE_HISTORY)
cindex(csh, history style)
cindex(history style, csh)
item(tt(CSH_JUNKIE_HISTORY) <C>)(
A history reference without an event specifier will always refer to the
previous command.  Without this option, such a history reference refers
to the same event as the previous history reference, defaulting to the
previous command.
)
pindex(CSH_JUNKIE_LOOPS)
cindex(csh, loop style)
cindex(loop style, csh)
item(tt(CSH_JUNKIE_LOOPS) <C>)(
Allow loop bodies to take the form `var(list); tt(end)' instead of
`tt(do) var(list); tt(done)'.
)
pindex(CSH_JUNKIE_QUOTES)
cindex(csh, quoting style)
cindex(quoting style, csh)
item(tt(CSH_JUNKIE_QUOTES) <C>)(
Changes the rules for single- and double-quoted text to match that of
bf(csh).  These require that embedded newlines be preceded by a backslash;
unescaped newlines will cause an error message.
In double-quoted strings, it is made impossible to escape `tt($)', `tt(`)'
or `tt(")' (and `tt(\)' itself no longer needs escaping).
Command substitutions are only expanded once, and cannot be nested.
)
pindex(CSH_NULLCMD)
vindex(NULLCMD, ignoring)
vindex(READNULLCMD, ignoring)
cindex(redirections with no command, csh)
cindex(csh, redirections with no command)
item(tt(CSH_NULLCMD) <C>)(
Do not use the values of tt(NULLCMD) and tt(READNULLCMD) 
when running redirections with no command.  This make 
such redirections fail (see noderef(Redirection)).
)
pindex(KSH_ARRAYS)
cindex(arrays, ksh style)
cindex(array style, ksh)
cindex(ksh, array style)
item(tt(KSH_ARRAYS) <K> <S>)(
Emulate bf(ksh) array handling as closely as possible.  If this option
is set, array elements are numbered from zero, an array parameter
without subscript refers to the first element instead of the whole array,
and braces are required to delimit a subscript (`tt(${path[2]})' rather
than just `tt($path[2])').
)
pindex(KSH_AUTOLOAD)
item(tt(KSH_AUTOLOAD) <K> <S>)(
Emulate bf(ksh) function autoloading.  This means that when a function is
autoloaded, the corresponding file is merely executed, and must define
the function itself.  (By default, the function is defined to the contents
of the file.  However, the most common bf(ksh)-style case - of the file
containing only a simple definition of the function - is always handled
in the bf(ksh)-compatible manner.)
)
pindex(KSH_OPTION_PRINT)
cindex(option printing, ksh style)
cindex(option printing style, ksh)
cindex(ksh, option printing style)
item(tt(KSH_OPTION_PRINT) <K>)(
Alters the way options settings are printed: instead of separate lists of
set and unset options, all options are shown, marked `on' if
they are in the non-default state, `off' otherwise.
)
pindex(KSH_TYPESET)
cindex(argument splitting, in typeset etc.)
cindex(ksh, argument splitting in typeset)
item(tt(KSH_TYPESET) <K>)(
Alters the way arguments to the tt(typeset) family of commands, including
tt(declare), tt(export), tt(float), tt(integer), tt(local) and
tt(readonly), are processed.  Without this option, zsh will perform normal
word splitting after command and parameter expansion in arguments of an
assignment; with it, word splitting does not take place in those cases.
)
pindex(KSH_ZERO_SUBSCRIPT)
cindex(arrays, behaviour of index zero)
item(tt(KSH_ZERO_SUBSCRIPT))(
Treat use of a subscript of value zero in array or string expressions as a
reference to the first element, i.e. the element that usually has the
subscript 1.  Ignored if tt(KSH_ARRAYS) is also set.

If neither this option nor tt(KSH_ARRAYS) is set, accesses to an element of
an array or string with subscript zero return an empty element or string,
while attempts to set element zero of an array or string are treated as an
error.  However, attempts to set an otherwise valid subscript range that
includes zero will succeed.  For example, if tt(KSH_ZERO_SUBSCRIPT) is not
set,

example(array[0]=(element))

is an error, while

example(array[0,1]=(element))

is not and will replace the first element of the array.

This option is for compatibility with older versions of the shell and
is not recommended in new code.
)
pindex(POSIX_BUILTINS)
item(tt(POSIX_BUILTINS) <K> <S>)(
When this option is set the tt(command) builtin can be used to execute
shell builtin commands.  Parameter assignments specified before shell
functions and special builtins are kept after the command completes unless
the special builtin is prefixed with the tt(command) builtin.  Special
builtins are
tt(.),
tt(:),
tt(break),
tt(continue),
tt(declare),
tt(eval),
tt(exit),
tt(export),
tt(integer),
tt(local),
tt(readonly),
tt(return),
tt(set),
tt(shift),
tt(source),
tt(times),
tt(trap) and
tt(unset).
)
pindex(POSIX_IDENTIFIERS)
cindex(identifiers, non-portable characters in)
cindex(parameter names, non-portable characters in)
item(tt(POSIX_IDENTIFIERS) <K> <S>)(
When this option is set, only the ASCII characters tt(a) to tt(z), tt(A) to
tt(Z), tt(0) to tt(9) and tt(_) may be used in identifiers (names
of shell parameters and modules).

When the option is unset and multibyte character support is enabled (i.e. it
is compiled in and the option tt(MULTIBYTE) is set), then additionally any
alphanumeric characters in the local character set may be used in
identifiers.  Note that scripts and functions written with this feature are
not portable, and also that both options must be set before the script
or function is parsed; setting them during execution is not sufficient
as the syntax var(variable)tt(=)var(value) has already been parsed as
a command rather than an assignment.

If multibyte character support is not compiled into the shell this option is
ignored; all octets with the top bit set may be used in identifiers.
This is non-standard but is the traditional zsh behaviour.
)
pindex(SH_FILE_EXPANSION)
cindex(sh, expansion style)
cindex(expansion style, sh)
item(tt(SH_FILE_EXPANSION) <K> <S>)(
Perform filename expansion (e.g., ~ expansion) em(before)
parameter expansion, command substitution, arithmetic expansion
and brace expansion.
If this option is unset, it is performed em(after)
brace expansion, so things like `tt(~$USERNAME)' and
`tt(~{pfalstad,rc})' will work.
)
pindex(SH_NULLCMD)
vindex(NULLCMD, ignoring)
vindex(READNULLCMD, ignoring)
cindex(sh, redirections with no command)
cindex(ksh, redirections with no command)
cindex(redirections with no command, sh)
cindex(redirections with no command, ksh)
item(tt(SH_NULLCMD) <K> <S>)(
Do not use the values of tt(NULLCMD) and tt(READNULLCMD) 
when doing redirections, use `tt(:)' instead (see noderef(Redirection)).
)
pindex(SH_OPTION_LETTERS)
cindex(sh, single letter options style)
cindex(ksh, single letter options style)
cindex(single letter options, ksh style)
cindex(options, single letter, ksh style)
item(tt(SH_OPTION_LETTERS) <K> <S>)(
If this option is set the shell tries to interpret single letter options
(which are used with tt(set) and tt(setopt)) like bf(ksh) does.
This also affects the value of the tt(-) special parameter.
)
pindex(SH_WORD_SPLIT)
cindex(field splitting, sh style)
cindex(sh, field splitting style)
item(tt(SH_WORD_SPLIT) (tt(-y)) <K> <S>)(
Causes field splitting to be performed on unquoted parameter expansions.
Note that this option has nothing to do with word splitting.
(See noderef(Parameter Expansion).)
)
pindex(TRAPS_ASYNC)
cindex(traps, asynchronous)
item(tt(TRAPS_ASYNC))(
While waiting for a program to exit, handle signals and run traps
immediately.  Otherwise the trap is run after a child process has exited.
Note this does not affect the point at which traps are run for any case
other than when the shell is waiting for a child process.
)
enditem()

subsect(Shell State)
startitem()
pindex(INTERACTIVE)
item(tt(INTERACTIVE) (tt(-i), ksh: tt(-i)))(
This is an interactive shell.  This option is set upon initialisation if
the standard input is a tty and commands are being read from standard input.
(See the discussion of tt(SHIN_STDIN).)
This heuristic may be overridden by specifying a state for this option
on the command line.
The value of this option cannot be changed anywhere other than the command line.
)
pindex(LOGIN)
item(tt(LOGIN) (tt(-l), ksh: tt(-l)))(
This is a login shell.
If this option is not explicitly set, the shell is a login shell if
the first character of the tt(argv[0]) passed to the shell is a `tt(-)'.
)
pindex(PRIVILEGED)
cindex(privileged mode)
cindex(mode, privileged)
item(tt(PRIVILEGED) (tt(-p), ksh: tt(-p)))(
Turn on privileged mode. This is enabled automatically on startup if the
effective user (group) ID is not equal to the real user (group) ID.  Turning
this option off causes the effective user and group IDs to be set to the
real user and group IDs. This option disables sourcing user startup files.
If zsh is invoked as `tt(sh)' or `tt(ksh)' with this option set,
tt(/etc/suid_profile) is sourced (after tt(/etc/profile) on interactive
shells). Sourcing tt(~/.profile) is disabled and the contents of the
tt(ENV) variable is ignored. This option cannot be changed using the
tt(-m) option of tt(setopt) and tt(unsetopt), and changing it inside a
function always changes it globally regardless of the tt(LOCAL_OPTIONS)
option.
)
pindex(RESTRICTED)
cindex(restricted shell)
item(tt(RESTRICTED) (tt(-r)))(
Enables restricted mode.  This option cannot be changed using
tt(unsetopt), and setting it inside a function always changes it
globally regardless of the tt(LOCAL_OPTIONS) option.  See
noderef(Restricted Shell).
)
pindex(SHIN_STDIN)
item(tt(SHIN_STDIN) (tt(-s), ksh: tt(-s)))(
Commands are being read from the standard input.
Commands are read from standard input if no command is specified with
tt(-c) and no file of commands is specified.  If tt(SHIN_STDIN)
is set explicitly on the command line,
any argument that would otherwise have been
taken as a file to run will instead be treated as a normal positional
parameter.
Note that setting or unsetting this option on the command line does not
necessarily affect the state the option will have while the shell is
running - that is purely an indicator of whether on not commands are
em(actually) being read from standard input.
The value of this option cannot be changed anywhere other 
than the command line.
)
pindex(SINGLE_COMMAND)
cindex(single command)
pindex(INTERACTIVE, use of)
item(tt(SINGLE_COMMAND) (tt(-t), ksh: tt(-t)))(
If the shell is reading from standard input, it exits after a single command
has been executed.  This also makes the shell non-interactive, unless the
tt(INTERACTIVE) option is explicitly set on the command line.
The value of this option cannot be changed anywhere other than the command line.
)
enditem()

subsect(Zle)
startitem()
pindex(BEEP)
cindex(beep, enabling)
cindex(enabling the beep)
item(tt(BEEP) (tt(PLUS()B)) <D>)(
Beep on error in ZLE.
)
pindex(COMBINING_CHARS)
cindex(characters, (Unicode) combining)
cindex(combining characters (Unicode))
cindex(Unicode combining characters)
item(tt(COMBINING_CHARS))(
Assume that the terminal displays combining characters correctly.
Specifically, if a base alphanumeric character is followed by one or more
zero-width punctuation characters, assume that the zero-width characters
will be displayed as modifications to the base character within the
same width.  Not all terminals handle this.  If this option is not
set, zero-width characters are displayed separately with special
mark-up.

If this option is set, the pattern test tt([[:WORD:]]) matches a
zero-width punctuation character on the assumption that it will be
used as part of a word in combination with a word character.
Otherwise the base shell does not handle combining characters specially.
)
pindex(EMACS)
item(tt(EMACS))(
If ZLE is loaded, turning on this option has the equivalent effect
of `tt(bindkey -e)'.  In addition, the VI option is unset.
Turning it off has no effect.  The option setting is
not guaranteed to reflect the current keymap.  This option is
provided for compatibility; tt(bindkey) is the recommended interface.
)
pindex(OVERSTRIKE)
cindex(editor, overstrike mode)
cindex(overstrike mode, of editor)
item(tt(OVERSTRIKE))(
Start up the line editor in overstrike mode.
)
pindex(SINGLE_LINE_ZLE)
cindex(editor, single line mode)
item(tt(SINGLE_LINE_ZLE) (tt(-M)) <K>)(
Use single-line command line editing instead of multi-line.
)
pindex(VI)
item(tt(VI))(
If ZLE is loaded, turning on this option has the equivalent effect
of `tt(bindkey -v)'.  In addition, the EMACS option is unset.
Turning it off has no effect.  The option setting is
not guaranteed to reflect the current keymap.  This option is
provided for compatibility; tt(bindkey) is the recommended interface.
)
pindex(ZLE)
cindex(editor, enabling)
cindex(enabling the editor)
item(tt(ZLE) (tt(-Z)))(
Use the zsh line editor.  Set by default in interactive shells connected to
a terminal.
)
enditem()

texinode(Option Aliases)(Single Letter Options)(Description of Options)(Options)
sect(Option Aliases)
cindex(options, aliases)
Some options have alternative names.  These aliases are never used for
output, but can be used just like normal option names when specifying
options to the shell.

startitem()
pindex(BRACE_EXPAND)
item(tt(BRACE_EXPAND))(
em(NO_)tt(IGNORE_BRACES)
(ksh and bash compatibility)
)
pindex(DOT_GLOB)
item(tt(DOT_GLOB))(
tt(GLOB_DOTS)
(bash compatibility)
)
pindex(HASH_ALL)
item(tt(HASH_ALL))(
tt(HASH_CMDS)
(bash compatibility)
)
pindex(HIST_APPEND)
item(tt(HIST_APPEND))(
tt(APPEND_HISTORY)
(bash compatibility)
)
pindex(HIST_EXPAND)
item(tt(HIST_EXPAND))(
tt(BANG_HIST)
(bash compatibility)
)
pindex(LOG)
item(tt(LOG))(
em(NO_)tt(HIST_NO_FUNCTIONS)
(ksh compatibility)
)
pindex(MAIL_WARN)
item(tt(MAIL_WARN))(
tt(MAIL_WARNING)
(bash compatibility)
)
pindex(ONE_CMD)
item(tt(ONE_CMD))(
tt(SINGLE_COMMAND)
(bash compatibility)
)
pindex(PHYSICAL)
item(tt(PHYSICAL))(
tt(CHASE_LINKS)
(ksh and bash compatibility)
)
pindex(PROMPT_VARS)
item(tt(PROMPT_VARS))(
tt(PROMPT_SUBST)
(bash compatibility)
)
pindex(STDIN)
item(tt(STDIN))(
tt(SHIN_STDIN)
(ksh compatibility)
)
pindex(TRACK_ALL)
item(tt(TRACK_ALL))(
tt(HASH_CMDS)
(ksh compatibility)
)
enditem()
texinode(Single Letter Options)()(Option Aliases)(Options)
sect(Single Letter Options)
cindex(options, single letter)
cindex(single letter options)
subsect(Default set)
startsitem()
sitem(tt(-0))(CORRECT)
sitem(tt(-1))(PRINT_EXIT_VALUE)
sitem(tt(-2))(em(NO_)BAD_PATTERN)
sitem(tt(-3))(em(NO_)NOMATCH)
sitem(tt(-4))(GLOB_DOTS)
sitem(tt(-5))(NOTIFY)
sitem(tt(-6))(BG_NICE)
sitem(tt(-7))(IGNORE_EOF)
sitem(tt(-8))(MARK_DIRS)
sitem(tt(-9))(AUTO_LIST)
sitem(tt(-B))(em(NO_)BEEP)
sitem(tt(-C))(em(NO_)CLOBBER)
sitem(tt(-D))(PUSHD_TO_HOME)
sitem(tt(-E))(PUSHD_SILENT)
sitem(tt(-F))(em(NO_)GLOB)
sitem(tt(-G))(NULL_GLOB)
sitem(tt(-H))(RM_STAR_SILENT)
sitem(tt(-I))(IGNORE_BRACES)
sitem(tt(-J))(AUTO_CD)
sitem(tt(-K))(em(NO_)BANG_HIST)
sitem(tt(-L))(SUN_KEYBOARD_HACK)
sitem(tt(-M))(SINGLE_LINE_ZLE)
sitem(tt(-N))(AUTO_PUSHD)
sitem(tt(-O))(CORRECT_ALL)
sitem(tt(-P))(RC_EXPAND_PARAM)
sitem(tt(-Q))(PATH_DIRS)
sitem(tt(-R))(LONG_LIST_JOBS)
sitem(tt(-S))(REC_EXACT)
sitem(tt(-T))(CDABLE_VARS)
sitem(tt(-U))(MAIL_WARNING)
sitem(tt(-V))(em(NO_)PROMPT_CR)
sitem(tt(-W))(AUTO_RESUME)
sitem(tt(-X))(LIST_TYPES)
sitem(tt(-Y))(MENU_COMPLETE)
sitem(tt(-Z))(ZLE)
sitem(tt(-a))(ALL_EXPORT)
sitem(tt(-e))(ERR_EXIT)
sitem(tt(-f))(em(NO_)RCS)
sitem(tt(-g))(HIST_IGNORE_SPACE)
sitem(tt(-h))(HIST_IGNORE_DUPS)
sitem(tt(-i))(INTERACTIVE)
sitem(tt(-k))(INTERACTIVE_COMMENTS)
sitem(tt(-l))(LOGIN)
sitem(tt(-m))(MONITOR)
sitem(tt(-n))(em(NO_)EXEC)
sitem(tt(-p))(PRIVILEGED)
sitem(tt(-r))(RESTRICTED)
sitem(tt(-s))(SHIN_STDIN)
sitem(tt(-t))(SINGLE_COMMAND)
sitem(tt(-u))(em(NO_)UNSET)
sitem(tt(-v))(VERBOSE)
sitem(tt(-w))(CHASE_LINKS)
sitem(tt(-x))(XTRACE)
sitem(tt(-y))(SH_WORD_SPLIT)
endsitem()
subsect(sh/ksh emulation set)
startsitem()
sitem(tt(-C))(em(NO_)CLOBBER)
sitem(tt(-T))(TRAPS_ASYNC)
sitem(tt(-X))(MARK_DIRS)
sitem(tt(-a))(ALL_EXPORT)
sitem(tt(-b))(NOTIFY)
sitem(tt(-e))(ERR_EXIT)
sitem(tt(-f))(em(NO_)GLOB)
sitem(tt(-i))(INTERACTIVE)
sitem(tt(-l))(LOGIN)
sitem(tt(-m))(MONITOR)
sitem(tt(-n))(em(NO_)EXEC)
sitem(tt(-p))(PRIVILEGED)
sitem(tt(-r))(RESTRICTED)
sitem(tt(-s))(SHIN_STDIN)
sitem(tt(-t))(SINGLE_COMMAND)
sitem(tt(-u))(em(NO_)UNSET)
sitem(tt(-v))(VERBOSE)
sitem(tt(-x))(XTRACE)
endsitem()
subsect(Also note)
startsitem()
sitem(tt(-A))(Used by tt(set) for setting arrays)
sitem(tt(-b))(Used on the command line to specify end of option processing)
sitem(tt(-c))(Used on the command line to specify a single command)
sitem(tt(-m))(Used by tt(setopt) for pattern-matching option setting)
sitem(tt(-o))(Used in all places to allow use of long option names)
sitem(tt(-s))(Used by tt(set) to sort positional parameters)
endsitem()