Provided by: zsh-common_5.9-6ubuntu2_all bug

NAME

       zshoptions - zsh options

SPECIFYING OPTIONS

       Options are primarily referred to by name.  These names are case insensitive and underscores are ignored.
       For example, `allexport' is equivalent to `A__lleXP_ort'.

       The sense of an option name may be inverted by preceding it with `no', so `setopt No_Beep' is  equivalent
       to  `unsetopt  beep'.   This  inversion can only be done once, so `nonobeep' is not a synonym for `beep'.
       Similarly, `tify' is not a synonym for `nonotify' (the inversion of `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 sh/ksh (used when the SH_OPTION_LETTERS option is set).  The
       single letter options can be used on the shell command  line,  or  with  the  set,  setopt  and  unsetopt
       builtins, as normal Unix options preceded by `-'.

       The  sense  of the single letter options may be inverted by using `+' instead of `-'.  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,  `+n'  is  the short name of `exec', and `-n' is the short name of its
       inversion, `noexec'.

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

       It  is  possible  for  options  to  be  set  within  a function scope.  See the description of the option
       LOCAL_OPTIONS below.

DESCRIPTION OF OPTIONS

       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 `setopt', `unsetopt', `set -o' or `set +o'), those turned on by default appear in the  list  prefixed
       with `no'.  Hence (unless KSH_OPTION_PRINT is set), `setopt' shows all options whose settings are changed
       from the default.

   Changing Directories
       AUTO_CD (-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  cd  command to that directory.  This option is only applicable if the
              option SHIN_STDIN is set, i.e. if commands are being read from  standard  input.   The  option  is
              designed  for  interactive  use;  it is recommended that cd be used explicitly in scripts to avoid
              ambiguity.

       AUTO_PUSHD (-N)
              Make cd push the old directory onto the directory stack.

       CDABLE_VARS (-T)
              If the argument to a cd command (or an implied cd with the 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 `~' (see
              the section `Filename Expansion').

       CD_SILENT
              Never print the working directory after a cd (whether explicit or implied with the AUTO_CD  option
              set). cd normally prints the working directory when the argument given to it was -, a stack entry,
              or the name of  a  directory  found  under  CDPATH.  Note  that  this  is  distinct  from  pushd's
              stack-printing  behaviour,  which  is  controlled  by  PUSHD_SILENT.  This  option  overrides  the
              printing-related effects of POSIX_CD.

       CHASE_DOTS
              When changing to a directory containing a path segment `..' which would otherwise  be  treated  as
              canceling  the  previous  segment  in the path (in other words, `foo/..' would be removed from the
              path, or if `..' is the first part of the path, the last part of  the  current  working  directory
              would  be removed), instead resolve the path to the physical directory.  This option is overridden
              by CHASE_LINKS.

              For example, suppose /foo/bar is a link to the directory /alt/rod.  Without this option  set,  `cd
              /foo/bar/..'  changes  to  /foo; with it set, it changes to /alt.  The same applies if the current
              directory is /foo/bar and `cd ..' is used.  Note that all other symbolic links in  the  path  will
              also be resolved.

       CHASE_LINKS (-w)
              Resolve  symbolic links to their true values when changing directory.  This also has the effect of
              CHASE_DOTS, i.e. a `..' path segment will be treated as referring to the physical parent, even  if
              the preceding path segment is a symbolic link.

       POSIX_CD <K> <S>
              Modifies the behaviour of cd, chdir and pushd commands to make them more compatible with the POSIX
              standard. The behaviour with the option unset is described in the documentation for the cd builtin
              in  zshbuiltins(1).   If  the  option  is set, the shell does not test for directories beneath the
              local directory (`.') until after all directories in cdpath have been tested, and the cd and chdir
              commands do not recognise arguments of the form `{+|-}n' as directory stack entries.

              Also,  if  the  option is set, the conditions under which the shell prints the new directory after
              changing to it are modified.  It is no longer restricted to interactive shells (although  printing
              of  the  directory  stack  with  pushd  is  still limited to interactive shells); and any use of a
              component of CDPATH, including a `.' but excluding an empty component that is otherwise treated as
              `.', causes the directory to be printed.

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

       PUSHD_MINUS
              Exchanges the meanings of `+' and `-' when used with a number to specify a directory in the stack.

       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'.

   Completion
       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 no numeric argument.

       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.

       AUTO_LIST (-9) <D>
              Automatically list choices on an ambiguous completion.

       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 MENU_COMPLETE.

       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 `%~' and related prompt sequences, and will be available  when
              completion  is  performed  on a word starting with `~'.  (Otherwise, the parameter must be used in
              the form `~param' first.)

       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 `}', `:', 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 `,', which will be removed if `}' is typed next.

       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.

       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.

       BASH_AUTO_LIST
              On  an  ambiguous  completion,  automatically  list choices when the completion function is called
              twice in succession.  This takes precedence over AUTO_LIST.   The  setting  of  LIST_AMBIGUOUS  is
              respected.   If  AUTO_MENU  is set, the menu behaviour will then start with the third press.  Note
              that this will not work with MENU_COMPLETE, since  repeated  completion  calls  immediately  cycle
              through the list in that case.

       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.

       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.

       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 MENU_COMPLETE. The matches  are
              generated  as  if  a  `*'  was  added  to  the  end  of  the  word, or inserted at the cursor when
              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 GLOB_COMPLETE option does not have this effect.

       HASH_LIST_ALL <D>
              Whenever  a  command  completion or spelling correction is attempted, make sure the entire command
              path is hashed first.  This makes the first completion slower but avoids false reports of spelling
              errors.

       LIST_AMBIGUOUS <D>
              This option works when AUTO_LIST or 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
              BASH_AUTO_LIST, this means that the list will be delayed to the third call of the function.

       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 BEEP is also
              set; this may be modified if completion is called from a user-defined widget.

       LIST_PACKED
              Try to make the completion list smaller (occupying less lines) by printing the matches in  columns
              with different widths.

       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.

       LIST_TYPES (-X) <D>
              When listing files that are possible completions, show the type  of  each  file  with  a  trailing
              identifying mark.

       MENU_COMPLETE (-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.
              reverse-menu-complete may be used to loop through the list in the  other  direction.  This  option
              overrides AUTO_MENU.

       REC_EXACT (-S)
              If the string on the command line exactly matches one of the possible completions, it is accepted,
              even if there is another completion (i.e.  that  string  with  something  else  added)  that  also
              matches.

   Expansion and Globbing
       BAD_PATTERN (+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.)

       BARE_GLOB_QUAL <Z>
              In a glob pattern, treat a trailing set of parentheses as a qualifier list, if it contains no `|',
              `(' or (if special) `~' characters.  See the section `Filename Generation'.

       BRACE_CCL
              Expand  expressions  in  braces  which  would not otherwise undergo brace expansion to a lexically
              ordered list of all the characters.  See the section `Brace Expansion'.

       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, cvs(/)  can  match  the
              directory  CVS  owing  to  the  presence of the globbing flag (unless the option BARE_GLOB_QUAL is
              unset).

       CASE_MATCH <D>
              Make regular expressions using the zsh/regex module (including matches with =~) sensitive to case.

       CASE_PATHS
              If CASE_PATHS is not set (the  default),  CASE_GLOB  affects  the  interpretation  of  every  path
              component,  whenever  a  special character appears in any component.  When CASE_PATHS is set, file
              path components that do not contain special filename generation characters are always sensitive to
              case, thus restricting NO_CASE_GLOB to components that contain globbing characters.

              Note that if the filesystem itself is not sensitive to case, then CASE_PATHS has no effect.

       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 NOMATCH.

       EQUALS <Z>
              Perform = filename expansion.  (See the section `Filename Expansion'.)

       EXTENDED_GLOB
              Treat the `#', `~' and `^' characters as part of  patterns  for  filename  generation,  etc.   (An
              initial unquoted `~' always produces named directory expansion.)

       FORCE_FLOAT
              Constants  in  arithmetic  evaluation  will be treated as floating point even without the use of a
              decimal point; the values of integer variables will be converted to floating point  when  used  in
              arithmetic expressions.  Integers in any base will be converted.

       GLOB (+F, ksh: +f) <D>
              Perform filename generation (globbing).  (See the section `Filename Generation'.)

       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 `name=pattern (e.g. `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 `name=(value)' (e.g. `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.

       GLOB_DOTS (-4)
              Do not require a leading `.' in a filename to be matched explicitly.

       GLOB_STAR_SHORT
              When this option is set and the default zsh-style globbing is in effect, the pattern `**/*' can be
              abbreviated to `**' and the pattern `***/*' can be abbreviated to ***.  Hence `**.c' finds a  file
              ending  in  .c in any subdirectory, and `***.c' does the same while also following symbolic links.
              A / immediately after the `**' or `***' forces the pattern to  be  treated  as  the  unabbreviated
              form.

       GLOB_SUBST <C> <K> <S>
              Treat  any  characters resulting from parameter expansion as being eligible for filename 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.

       HIST_SUBST_PATTERN
              Substitutions using the :s and :& history modifiers are performed with pattern matching instead of
              string matching.  This occurs wherever history modifiers are valid, including glob qualifiers  and
              parameters.  See the section `Modifiers' in zshexpn(1).

       IGNORE_BRACES (-I) <S>
              Do  not  perform  brace  expansion.   For  historical reasons this also includes the effect of the
              IGNORE_CLOSE_BRACES option.

       IGNORE_CLOSE_BRACES
              When neither this  option  nor  IGNORE_BRACES  is  set,  a  sole  close  brace  character  `}'  is
              syntactically  significant  at any point on a command line.  This has the effect that no semicolon
              or newline is necessary before the brace terminating a function or current shell construct.   When
              either  option  is  set,  a  closing  brace is syntactically significant only in command position.
              Unlike IGNORE_BRACES, this option does not disable brace expansion.

              For example, with both options unset a function may be defined in the following fashion:

                     args() { echo $# }

              while if either option is set, this does not work and something equivalent  to  the  following  is
              required:

                     args() { echo $#; }

       KSH_GLOB <K>
              In  pattern  matching, the interpretation of parentheses is affected by a preceding `@', `*', `+',
              `?' or `!'.  See the section `Filename Generation'.

       MAGIC_EQUAL_SUBST
              All unquoted arguments of the form `anything=expression' appearing after  the  command  name  have
              filename expansion (that is, where expression has a leading `~' or `=') performed on 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 echo foo=~/bar:~/rod, both occurrences of ~ would be replaced.  Note that this  happens  anyway
              with typeset and similar statements.

              This  option  respects the setting of the KSH_TYPESET option.  In other words, if both options are
              in effect, arguments looking like assignments will not undergo word splitting.

       MARK_DIRS (-8, ksh: -X)
              Append a trailing `/' to all directory names resulting from filename generation (globbing).

       MULTIBYTE <D>
              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 MULTIBYTE_SUPPORT; otherwise it is off
              by default and has no effect if turned on.

              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.

       NOMATCH (+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 `~' or `='.

       NULL_GLOB (-G)
              If a pattern for filename generation has no matches, delete the pattern  from  the  argument  list
              instead of reporting an error.  Overrides NOMATCH.

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

       RC_EXPAND_PARAM (-P)
              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'.  Note that an
              empty array will therefore cause all arguments to be removed.

       REMATCH_PCRE
              If set, regular expression  matching  with  the  =~  operator  will  use  Perl-Compatible  Regular
              Expressions  from the PCRE library.  (The zsh/pcre module must be available.)  If not set, regular
              expressions will use the extended regexp syntax provided by the system libraries.

       SH_GLOB <K> <S>
              Disables the special meaning of `(', `|', `)' and '<' for globbing the  result  of  parameter  and
              command  substitutions,  and in some other places where the shell accepts patterns.  If SH_GLOB is
              set but KSH_GLOB is not, the shell allows the interpretation of subshell expressions  enclosed  in
              parentheses  in some cases where there is no space before the opening parenthesis, e.g. !(true) is
              interpreted as if there were a space after the !.  This option is set by default if zsh is invoked
              as sh or ksh.

       UNSET (+u, ksh: +u) <K> <S> <Z>
              Treat  unset  parameters  as  if  they were empty when substituting, and as if they were zero when
              reading their values in arithmetic expansion and arithmetic commands.  Otherwise they are  treated
              as an error.

       WARN_CREATE_GLOBAL
              Print  a  warning  message when a global parameter is created in a function by an assignment or in
              math context.  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 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.

       WARN_NESTED_VAR
              Print a warning message when an existing parameter from an enclosing function scope, or global, is
              set in a function by an assignment or in math context.  Assignment  to  shell  special  parameters
              does not cause a warning.  This is the companion to WARN_CREATE_GLOBAL as in this case the warning
              is only printed when a parameter is not created.  Where possible, use of typeset  -g  to  set  the
              parameter  suppresses  the  error, but note that this needs to be used every time the parameter is
              set.  To restrict the effect of this option to a single function scope, use `functions -W'.

              For example, the following code produces a warning for the assignment inside the  function  nested
              as that overrides the value within toplevel

                     toplevel() {
                       local foo="in fn"
                       nested
                     }
                     nested() {
                          foo="in nested"
                     }
                     setopt warn_nested_var
                     toplevel

   History
       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  $SAVEHIST
              (see also the HIST_SAVE_BY_COPY option).

       BANG_HIST (+K) <C> <Z>
              Perform textual history expansion, csh-style, treating the character `!' specially.

       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:

              `: <beginning time>:<elapsed seconds>;<command>'.

       HIST_ALLOW_CLOBBER
              Add `|' to output redirections in the history.  This allows history references  to  clobber  files
              even when CLOBBER is unset.

       HIST_BEEP <D>
              Beep in ZLE when a widget attempts to access a history entry which isn't there.

       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 HISTSIZE to a larger number than SAVEHIST
              in order to give you some room for the duplicated events, otherwise this option will  behave  just
              like HIST_IGNORE_ALL_DUPS once the history fills up with unique events.

       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
              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.

       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.

       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).

       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)
              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.  Only normal aliases (not global or
              suffix aliases) have this behaviour.  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.

       HIST_LEX_WORDS
              By default, shell history that is read in from files is split into words on all white space.  This
              means that arguments with quoted whitespace are not correctly handled, with the  consequence  that
              references to words in history lines that have been read from a file may be inaccurate.  When this
              option is set, words read in from a history file are divided up in a  similar  fashion  to  normal
              shell  command line handling.  Although this produces more accurately delimited words, if the size
              of the history file is large this can be slow.  Trial and error is necessary to decide.

       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.

       HIST_NO_STORE
              Remove the history (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.

       HIST_REDUCE_BLANKS
              Remove superfluous blanks from each command line being added to the history list.

       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.

       HIST_SAVE_NO_DUPS
              When writing out the history file, older commands that duplicate newer ones are omitted.

       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.

       INC_APPEND_HISTORY
              This  option  works  like  APPEND_HISTORY except that new history lines are added to the $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 $SAVEHIST (see also the HIST_SAVE_BY_COPY option).

       INC_APPEND_HISTORY_TIME
              This option is a variant of INC_APPEND_HISTORY in which, where  possible,  the  history  entry  is
              written  out  to  the file after the command is finished, so that the time taken by the command is
              recorded correctly in the history file in EXTENDED_HISTORY format.  This means  that  the  history
              entry  will not be available immediately from other instances of the shell that are using the same
              history file.

              This option is only useful if INC_APPEND_HISTORY and SHARE_HISTORY  are  turned  off.   The  three
              options should be considered mutually exclusive.

       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 INC_APPEND_HISTORY, which should
              be turned off if this option is in effect).  The history lines are also output with timestamps ala
              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
              SHARE_HISTORY off, INC_APPEND_HISTORY or INC_APPEND_HISTORY_TIME (see above) on, and then manually
              import commands whenever you need them using `fc -RI'.

   Initialisation
       ALL_EXPORT (-a, ksh: -a)
              All parameters subsequently defined are automatically exported.

       GLOBAL_EXPORT <Z>
              If  this  option is set, passing the -x flag to the builtins declare, float, integer, readonly and
              typeset (but not local) will also set the -g flag;  hence parameters exported to  the  environment
              will not be made local to the enclosing function, unless they were already or the flag +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 export always sets both the -x and -g flags, and hence  its
              effect  extends  beyond  the  scope  of  the  enclosing function; this is the most portable way to
              achieve this behaviour.

       GLOBAL_RCS (+d) <D>
              If this option is unset, the startup files /etc/zsh/zprofile, /etc/zsh/zshrc, /etc/zsh/zlogin  and
              /etc/zsh/zlogout will not be run.  It can be disabled and re-enabled at any time, including inside
              local startup files (.zshrc, etc.).

       RCS (+f) <D>
              After /etc/zsh/zshenv is sourced on startup, source  the  .zshenv,  /etc/zsh/zprofile,  .zprofile,
              /etc/zsh/zshrc,  .zshrc, /etc/zsh/zlogin, .zlogin, and .zlogout files, as described in the section
              `Files'.  If this option is unset, the /etc/zsh/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.

   Input/Output
       ALIASES <D>
              Expand aliases.

       CLOBBER (+C, ksh: +C) <D>
              Allows `>' redirection to truncate existing files.   Otherwise  `>!'  or  `>|'  must  be  used  to
              truncate a file.

              If  the  option  is  not set, and the option APPEND_CREATE is also not set, `>>!' or `>>|' must be
              used to create a file.  If either option is set, `>>' may be used.

       CLOBBER_EMPTY
              This option is only used if the option CLOBBER is not set: note that it is set by default.

              If this option is set, then regular files of zero length may be  ovewritten  (`clobbered').   Note
              that  it is possible another process has written to the file between this test and use of the file
              by the current process.  This option should therefore not be used  in  cases  where  files  to  be
              clobbered may be written to asynchronously.

       CORRECT (-0)
              Try  to  correct the spelling of commands.  Note that, when the 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.

              The  shell  variable  CORRECT_IGNORE  may  be  set  to a pattern to match words that will never be
              offered as corrections.

       CORRECT_ALL (-O)
              Try to correct the spelling of all arguments in a line.

              The shell variable CORRECT_IGNORE_FILE may be set to a pattern to match file names that will never
              be offered as corrections.

       DVORAK Use  the Dvorak keyboard instead of the standard qwerty keyboard as a basis for examining spelling
              mistakes for the CORRECT and CORRECT_ALL options and the spell-word editor command.

       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.

       IGNORE_EOF (-7)
              Do  not exit on end-of-file.  Require the use of exit or 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.

       INTERACTIVE_COMMENTS (-k) <K> <S>
              Allow comments even in interactive shells.

       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 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.

       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 HASH_CMDS nor CORRECT is set.

       HASH_EXECUTABLES_ONLY
              When  hashing  commands  because  of  HASH_CMDS,  check  that the file to be hashed is actually an
              executable.  This option is unset by default as if the path contains a large number  of  commands,
              or  consists  of many remote files, the additional tests can take a long time.  Trial and error is
              needed to show if this option is beneficial.

       MAIL_WARNING (-U)
              Print a warning message if a mail file has been accessed since the shell last checked.

       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 or she types `X11/xinit', the command `/usr/local/bin/X11/xinit' will be
              executed (assuming it exists).  Commands explicitly beginning with `/',  `./'  or  `../'  are  not
              subject to the path search.  This also applies to the `.' and source builtins.

              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
              `.' or the current directory appear in the command search path.

       PATH_SCRIPT <K> <S>
              If  this  option  is  not  set, a script passed as the first non-option argument to the shell must
              contain the name of the file to open.  If this option is set, and the script does  not  specify  a
              directory path, the script is looked for first in the current directory, then in the command path.
              See the section INVOCATION in zsh(1).

       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 ctype(3)).

       PRINT_EXIT_VALUE (-1)
              Print the exit value of programs with non-zero exit status.  This is only available at the command
              line in interactive shells.

       RC_QUOTES
              Allow the character sequence `''' to signify a single quote within singly  quoted  strings.   Note
              this  does  not  apply in quoted strings using the format $'...', where a backslashed single quote
              can be used.

       RM_STAR_SILENT (-H) <K> <S>
              Do not query the user before executing `rm *' or `rm path/*'.

       RM_STAR_WAIT
              If querying the user before executing `rm *' or `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 `*'  in
              ZLE (with tab).

       SHORT_LOOPS <C> <Z>
              Allow the short forms of for, repeat, select, if, and function constructs.

       SHORT_REPEAT
              Allow the short form repeat as SHORT_LOOPS but without enabling it for the other constructs.

       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.  As an alternative the variable KEYBOARD_HACK lets you
              choose the character to be removed.

   Job Control
       AUTO_CONTINUE
              With this option set, stopped jobs that are removed from the job table  with  the  disown  builtin
              command are automatically sent a CONT signal to make them running.

       AUTO_RESUME (-W)
              Treat  single word simple commands without redirection as candidates for resumption of an existing
              job.

       BG_NICE (-6) <C> <Z>
              Run all background jobs at a lower priority.  This option is set by default.

       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.  NO_CHECK_JOBS is best used only in combination
              with NO_HUP, else such jobs will be killed automatically.

              The check is omitted if the commands run from the previous command line included a `jobs' command,
              since  it  is  assumed  the  user  is aware that there are background or suspended jobs.  A `jobs'
              command run from one of the hook functions defined in the section SPECIAL FUNCTIONS in  zshmisc(1)
              is not counted for this purpose.

       CHECK_RUNNING_JOBS <Z>
              Check  for  both  running  and  suspended  jobs  when  CHECK_JOBS is enabled.  When this option is
              disabled, zsh checks only for suspended jobs, which matches the default behavior of bash.

              This option has no effect unless CHECK_JOBS is set.

       HUP <Z>
              Send the HUP signal to running jobs when the shell exits.

       LONG_LIST_JOBS (-R)
              Print job notifications in the long format by default.

       MONITOR (-m, ksh: -m)
              Allow job control.  Set by default in interactive shells.

       NOTIFY (-5, ksh: -b) <Z>
              Report the status of background jobs immediately, rather than waiting until just before printing a
              prompt.

       POSIX_JOBS <K> <S>
              This option makes job control more compliant with the POSIX standard.

              When the option is not set, the MONITOR option is unset on entry to subshells, so that job control
              is no longer active.  When the option is set, the MONITOR option and job control remain active  in
              the subshell, but note that the subshell has no access to jobs in the parent shell.

              When  the  option is not set, jobs put in the background or foreground with bg or fg are displayed
              with the same information that would be reported by jobs.  When the option is set, only  the  text
              is printed.  The output from jobs itself is not affected by the option.

              When  the  option  is  not set, job information from the parent shell is saved for output within a
              subshell (for example, within a pipeline).  When the option is set, the output of  jobs  is  empty
              until a job is started within the subshell.

              In  previous versions of the shell, it was necessary to enable POSIX_JOBS in order for the builtin
              command wait to return the status of background jobs that had already exited.  This is  no  longer
              the case.

   Prompting
       PROMPT_BANG <K>
              If  set,  `!'  is  treated  specially  in  prompt expansion.  See EXPANSION OF PROMPT SEQUENCES in
              zshmisc(1).

       PROMPT_CR (+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.

       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, by default you will see an inverse+bold character at the end of
              the partial line:  a `%' for a normal user or a  `#'  for  root.   If  set,  the  shell  parameter
              PROMPT_EOL_MARK can be used to customize how the end of partial lines are shown.

              NOTE:  if  the PROMPT_CR option is not set, enabling this option will have no effect.  This option
              is on by default.

       PROMPT_PERCENT <C> <Z>
              If set, `%' is treated specially in prompt  expansion.   See  EXPANSION  OF  PROMPT  SEQUENCES  in
              zshmisc(1).

       PROMPT_SUBST <K> <S>
              If  set,  parameter  expansion,  command  substitution  and  arithmetic expansion are performed in
              prompts.  Substitutions within prompts do not affect the command status.

       TRANSIENT_RPROMPT
              Remove any right prompt from display when accepting a command  line.   This  may  be  useful  with
              terminals with other cut/paste methods.

   Scripts and Functions
       ALIAS_FUNC_DEF <S>
              By  default, zsh does not allow the definition of functions using the `name ()' syntax if name was
              expanded as an alias: this causes an error.  This is usually the desired behaviour,  as  otherwise
              the combination of an alias and a function based on the same definition can easily cause problems.

              When this option is set, aliases can be used for defining functions.

              For example, consider the following definitions as they might occur in a startup file.

                     alias foo=bar
                     foo() {
                       print This probably does not do what you expect.
                     }

              Here,  foo  is  expanded  as an alias to bar before the () is encountered, so the function defined
              would be named bar.  By default this is instead an error in native mode.  Note  that  quoting  any
              part  of  the  function name, or using the keyword function, avoids the problem, so is recommended
              when the function name can also be an alias.

       C_BASES
              Output hexadecimal numbers in the standard C format, for  example  `0xFF'  instead  of  the  usual
              `16#FF'.   If  the  option  OCTAL_ZEROES is also set (it is not by default), octal numbers will be
              treated similarly and hence appear as `077' instead of `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 C_BASES.

       C_PRECEDENCES
              This alters the precedence of arithmetic operators  to  be  more  like  C  and  other  programming
              languages; the section ARITHMETIC EVALUATION in zshmisc(1) has an explicit list.

       DEBUG_BEFORE_CMD <D>
              Run  the  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.

       ERR_EXIT (-e, ksh: -e)
              If a command has a non-zero exit status, execute the  ZERR  trap,  if  set,  and  exit.   This  is
              disabled while running initialization scripts.

              The  behaviour is also disabled inside DEBUG traps.  In this case the option is handled specially:
              it is unset on entry to the trap.  If the option DEBUG_BEFORE_CMD is set, as it is by default, and
              the  option  ERR_EXIT is found to have been set on exit, then the command for which the DEBUG trap
              is being executed is skipped.  The option is restored after the trap exits.

              Non-zero status in a command list containing && or || is ignored for commands not at  the  end  of
              the list.  Hence

                     false && true

              does not trigger exit.

              Exiting  due to ERR_EXIT has certain interactions with asynchronous jobs noted in the section JOBS
              in zshmisc(1).

       ERR_RETURN
              If a command has a non-zero exit status, return immediately  from  the  enclosing  function.   The
              logic  is  similar  to  that  for  ERR_EXIT,  except that an implicit return statement is executed
              instead of an exit.  This will trigger an exit at the outermost level of a non-interactive script.

              Normally this option inherits the behaviour of ERR_EXIT that code followed by `&&' `||'  does  not
              trigger a return.  Hence in the following:

                     summit || true

              no return is forced as the combined effect always has a zero return status.

              Note.  however,  that  if  summit  in  the  above  example is itself a function, code inside it is
              considered separately: it may force a return from summit (assuming the option remains  set  within
              summit),  but  not from the enclosing context.  This behaviour is different from ERR_EXIT which is
              unaffected by function scope.

       EVAL_LINENO <Z>
              If set, line numbers of expressions evaluated using the builtin eval are tracked separately of the
              enclosing  environment.   This  applies both to the parameter LINENO and the line number output by
              the prompt escape %i.  If the option is set, the prompt escape %N will output the string  `(eval)'
              instead  of  the script or function name as an indication.   (The two prompt escapes are typically
              used in the parameter PS4 to be output when the option XTRACE is set.)  If EVAL_LINENO  is  unset,
              the line number of the surrounding script or function is retained during the evaluation.

       EXEC (+n, ksh: +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  `-n'  is
              supplied to the shell at startup.

       FUNCTION_ARGZERO <C> <Z>
              When  executing  a  shell  function  or  sourcing  a script, set $0 temporarily to the name of the
              function/script.  Note that toggling FUNCTION_ARGZERO from on to off  (or  off  to  on)  does  not
              change  the  current  value  of  $0.   Only  the state upon entry to the function or script has an
              effect.  Compare POSIX_ARGZERO.

       LOCAL_LOOPS
              When this option is not set, the effect of break  and  continue  commands  may  propagate  outside
              function  scope,  affecting  loops  in  calling  functions.   When  the option is set in a calling
              function, a break or a continue that is not caught within a called  function  (regardless  of  the
              setting of the option within that function) produces a warning and the effect is cancelled.

       LOCAL_OPTIONS <K>
              If  this  option is set at the point of return from a shell function, most options (including this
              one) which were in force upon entry to the function are restored; options that  are  not  restored
              are  PRIVILEGED  and  RESTRICTED.   Otherwise,  only  this option, and the LOCAL_LOOPS, XTRACE and
              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 `emulate  -L  zsh';  the  -L  activates
              LOCAL_OPTIONS.

       LOCAL_PATTERNS
              If this option is set at the point of return from a shell function, the state of pattern disables,
              as set with the builtin command `disable -p', is restored to what it was  when  the  function  was
              entered.  The behaviour of this option is similar to the effect of LOCAL_OPTIONS on options; hence
              `emulate -L sh' (or indeed any other emulation with the -L option) activates LOCAL_PATTERNS.

       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
              prior to altering the trap behaviour in a function; unlike 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,

                     unsetopt localtraps
                     trap - INT
                     fn() { setopt localtraps; trap '' INT; sleep 3; }

              will restore normal handling of SIGINT after the function exits.

       MULTI_FUNC_DEF <Z>
              Allow definitions of multiple functions at once in the form `fn1 fn2...()'; if the option  is  not
              set,  this  causes  a  parse error.  Definition of multiple functions with the function keyword is
              always allowed.  Multiple function definitions are not often used and can cause obscure errors.

       MULTIOS <Z>
              Perform implicit  tees  or  cats  when  multiple  redirections  are  attempted  (see  the  section
              `Redirection').

       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 `08' component in `08#77' are always
              interpreted as decimal, regardless of leading zeroes.

       PIPE_FAIL
              By default, when a pipeline exits the exit status recorded by the shell and returned by the  shell
              variable $? reflects that of the rightmost element of a pipeline.  If this option is set, the exit
              status instead reflects the status of the rightmost element of the pipeline that was non-zero,  or
              zero if all elements exited with zero status.

       SOURCE_TRACE
              If  set,  zsh  will print an informational message announcing the name of each file it loads.  The
              format of the output is similar to that for the XTRACE option, with the message <sourcetrace>.   A
              file  may  be loaded by the shell itself when it starts up and shuts down (Startup/Shutdown Files)
              or by the use of the `source' and `dot' builtin commands.

       TYPESET_SILENT
              If this is unset, executing any of the `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
              `-m' option.  The option `-p' is available whether or not the option is set.

       TYPESET_TO_UNSET <K> <S>
              When declaring a new parameter with any of the `typeset' family of related commands, the parameter
              remains unset unless and until a value is explicitly assigned  to  it,  either  in  the  `typeset'
              command itself or as a later assignment statement.

       VERBOSE (-v, ksh: -v)
              Print shell input lines as they are read.

       XTRACE (-x, ksh: -x)
              Print  commands  and their arguments as they are executed.  The output is preceded by the value of
              $PS4, formatted as described in the section EXPANSION OF PROMPT SEQUENCES in zshmisc(1).

   Shell Emulation
       APPEND_CREATE <K> <S>
              This option only applies when NO_CLOBBER (-C) is in effect.

              If this option is not set, the shell will report an error when a append redirection (>>)  is  used
              on  a  file  that  does  not already exists (the traditional zsh behaviour of NO_CLOBBER).  If the
              option is set, no error is reported (POSIX behaviour).

       BASH_REMATCH
              When set, matches performed with the =~ operator will set the BASH_REMATCH array variable, instead
              of  the  default  MATCH  and  match  variables.   The first element of the BASH_REMATCH array will
              contain the entire matched text and subsequent elements will contain extracted  substrings.   This
              option  makes more sense when 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  MATCH  variable
              contains the entire matched text and the match array variable contains substrings.

       BSD_ECHO <S>
              Make  the  echo builtin compatible with the BSD echo(1) command.  This disables backslashed escape
              sequences in echo strings unless the -e option is specified.

       CONTINUE_ON_ERROR
              If a fatal error is encountered (see the section ERRORS in zshmisc(1)), and the code is running in
              a script, the shell will resume execution at the next statement in the script at the top level, in
              other words outside all functions or shell constructs such as loops and conditions.   This  mimics
              the  behaviour  of  interactive  shells,  where the shell returns to the line editor to read a new
              command; it was the normal behaviour in versions of zsh before 5.0.1.

       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
              on the current command line, defaulting to the previous command.

       CSH_JUNKIE_LOOPS <C>
              Allow loop bodies to take the form `list; end' instead of `do list; done'.

       CSH_JUNKIE_QUOTES <C>
              Changes the rules for single- and double-quoted text to match that of  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 `$', ``' or `"' (and `\' itself  no  longer
              needs escaping).  Command substitutions are only expanded once, and cannot be nested.

       CSH_NULLCMD <C>
              Do  not use the values of NULLCMD and READNULLCMD when running redirections with no command.  This
              make such redirections fail (see the section `Redirection').

       KSH_ARRAYS <K> <S>
              Emulate 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  (`${path[2]}'  rather  than  just
              `$path[2]') or to apply modifiers to any parameter (`${PWD:h}' rather than `$PWD:h').

       KSH_AUTOLOAD <K> <S>
              Emulate   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 ksh-style case - of the
              file containing only a simple definition of the function - is always handled in the ksh-compatible
              manner.)

       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.

       KSH_TYPESET
              This option is now obsolete: a better appropximation to the behaviour of other shells is  obtained
              with  the reserved word interface to declare, export, float, integer, local, readonly and typeset.
              Note that the option is only applied when the reserved word interface is not in use.

              Alters the way arguments to the typeset family of  commands,  including  declare,  export,  float,
              integer,  local  and  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.

       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 KSH_ARRAYS is also set.

              If neither this option nor 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 KSH_ZERO_SUBSCRIPT is not set,

                     array[0]=(element)

              is an error, while

                     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.

       POSIX_ALIASES <K> <S>
              When this option is set, reserved words are not candidates  for  alias  expansion:   it  is  still
              possible to declare any of them as an alias, but the alias will never be expanded.  Reserved words
              are described in the section RESERVED WORDS in zshmisc(1).

              Alias expansion takes place while text is being read; hence when this option is set  it  does  not
              take  effect  until the end of any function or other piece of shell code parsed as one unit.  Note
              this may cause differences from other shells even when the option is in effect.  For example, when
              running  a command with `zsh -c', or even `zsh -o posixaliases -c', the entire command argument is
              parsed as one unit, so aliases defined within the argument are not available even in later  lines.
              If in doubt, avoid use of aliases in non-interactive code.

       POSIX_ARGZERO
              This  option  may be used to temporarily disable FUNCTION_ARGZERO and thereby restore the value of
              $0 to the name used to invoke the  shell  (or  as  set  by  the  -c  command  line  option).   For
              compatibility  with  previous versions of the shell, emulations use NO_FUNCTION_ARGZERO instead of
              POSIX_ARGZERO, which may result in unexpected scoping of $0  if  the  emulation  mode  is  changed
              inside  a  function  or  script.   To  avoid  this, explicitly enable POSIX_ARGZERO in the emulate
              command:

                     emulate sh -o POSIX_ARGZERO

              Note that NO_POSIX_ARGZERO has no effect unless FUNCTION_ARGZERO was already enabled upon entry to
              the function or script.

       POSIX_BUILTINS <K> <S>
              When  this  option  is  set  the  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 command builtin.  Special
              builtins are ., :, break, continue, declare, eval, exit, export, integer, local, readonly, return,
              set, shift, source, times, trap and unset.

              In  addition,  various  error  conditions  associated  with  the  above  builtins  or exec cause a
              non-interactive shell to exit and an interactive shell to return to its top-level processing.

              Furthermore, functions and shell builtins are not executed after an exec prefix; the command to be
              executed must be an external command found in the path.

              Furthermore,  the  getopts  builtin  behaves  in a POSIX-compatible fashion in that the associated
              variable OPTIND is not made local to functions, and its value is calculated differently  to  match
              other shells.

              Moreover, the warning and special exit code from [[ -o non_existent_option ]] are suppressed.

       POSIX_IDENTIFIERS <K> <S>
              When  this  option  is  set, only the ASCII characters a to z, A to Z, 0 to 9 and _ may be used in
              identifiers (names of shell parameters and modules).

              In addition, setting this option limits the effect of parameter substitution with  no  braces,  so
              that  the expression $# is treated as the parameter $# even if followed by a valid parameter name.
              When it is unset, zsh allows expressions of the form $#name to refer to the length of $name,  even
              for special variables, for example in expressions such as $#- and $#*.

              Another  difference  is  that  with  the  option set assignment to an unset variable in arithmetic
              context causes the variable to be created as a scalar rather than a numeric type.  So after `unset
              t; (( t = 3 ))'. without POSIX_IDENTIFIERS set t has integer type, while with it set it has scalar
              type.

              When the option is unset and multibyte character support is enabled (i.e. it is  compiled  in  and
              the option 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 variable=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.

       POSIX_STRINGS <K> <S>
              This option affects processing of quoted strings.  Currently it only affects the behaviour of null
              characters, i.e. character 0 in the portable character set corresponding to US ASCII.

              When this option is not set, null characters embedded  within  strings  of  the  form  $'...'  are
              treated  as  ordinary  characters.  The entire string is maintained within the shell and output to
              files where necessary, although owing to restrictions of  the  library  interface  the  string  is
              truncated  at the null character in file names, environment variables, or in arguments to external
              programs.

              When this option is set, the $'...' expression is truncated at  the  null  character.   Note  that
              remaining parts of the same string beyond the termination of the quotes are not truncated.

              For  example, the command line argument a$'b\0c'd is treated with the option off as the characters
              a, b, null, c, d, and with the option on as the characters a, b, d.

       POSIX_TRAPS <K> <S>
              When this option is set, the usual zsh behaviour of executing traps for EXIT on  exit  from  shell
              functions  is suppressed.  In that case, manipulating EXIT traps always alters the global trap for
              exiting the shell; the LOCAL_TRAPS option is ignored for the EXIT trap.

              Also, a return statement executed in a trap with no argument passes back  from  the  function  the
              value from the surrounding context, not from code executed within the trap.

              Furthermore,  if  a  trap  is  set  to be ignored, this state persists when a subshell is entered.
              Without the option, the trap would be reset to its default state at this point.

       SH_FILE_EXPANSION <K> <S>
              Perform filename expansion (e.g., ~ expansion) before parameter expansion,  command  substitution,
              arithmetic  expansion  and  brace expansion.  If this option is unset, it is performed after brace
              expansion, so things like `~$USERNAME' and `~{pfalstad,rc}' will work.

       SH_NULLCMD <K> <S>
              Do not use the values of NULLCMD and READNULLCMD when doing redirections, use `:' instead (see the
              section `Redirection').

       SH_OPTION_LETTERS <K> <S>
              If  this option is set the shell tries to interpret single letter options (which are used with set
              and setopt) like ksh does.  This also affects the value of the - special parameter.

       SH_WORD_SPLIT (-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 zshexpn(1).)

       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.

   Shell State
       INTERACTIVE (-i, ksh: -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  SHIN_STDIN.)   This
              heuristic  may be overridden by specifying a state for this option on the command line.  The value
              of this option can only be changed via flags supplied at invocation of the shell.   It  cannot  be
              changed once zsh is running.

       LOGIN (-l, ksh: -l)
              This  is  a login shell.  If this option is not explicitly set, the shell becomes a login shell if
              the first character of the argv[0] passed to the shell is a `-'.

       PRIVILEGED (-p, ksh: -p)
              Turn on privileged mode. Typically this is used when script is to be run with elevated privileges.
              This  should  be done as follows directly with the -p option to zsh so that it takes effect during
              startup.

                     #!/bin/zsh -p

              The option is enabled automatically on startup if the effective user (group) ID is  not  equal  to
              the real user (group) ID. In this case, turning the option off causes the effective user and group
              IDs to be set to the real user and group IDs. Be aware that if that fails the shell may be running
              with different IDs than was intended so a script should check for failure and act accordingly, for
              example:

                     unsetopt privileged || exit

              The PRIVILEGED option disables sourcing user startup files.  If zsh is invoked as  `sh'  or  `ksh'
              with  this  option  set,  /etc/suid_profile is sourced (after /etc/profile on interactive shells).
              Sourcing ~/.profile is disabled and the contents of the  ENV  variable  is  ignored.  This  option
              cannot  be  changed  using the -m option of setopt and unsetopt, and changing it inside a function
              always changes it globally regardless of the LOCAL_OPTIONS option.

       RESTRICTED (-r)
              Enables restricted mode.  This option cannot be changed using unsetopt, and setting  it  inside  a
              function  always  changes  it  globally  regardless  of the LOCAL_OPTIONS option.  See the section
              `Restricted Shell'.

       SHIN_STDIN (-s, ksh: -s)
              Commands are being read from the standard input.  Commands are read  from  standard  input  if  no
              command  is  specified  with  -c  and  no  file  of  commands  is specified.  If 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 or not commands are actually being read
              from standard input.  The value of  this  option  can  only  be  changed  via  flags  supplied  at
              invocation of the shell.  It cannot be changed once zsh is running.

       SINGLE_COMMAND (-t, ksh: -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 INTERACTIVE option is explicitly set on  the
              command  line.   The  value of this option can only be changed via flags supplied at invocation of
              the shell.  It cannot be changed once zsh is running.

   Zle
       BEEP (+B) <D>
              Beep on error in ZLE.

       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 [[: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.

       EMACS  If ZLE is loaded, turning on this option has the equivalent effect of `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; bindkey is the recommended
              interface.

       OVERSTRIKE
              Start up the line editor in overstrike mode.

       SINGLE_LINE_ZLE (-M) <K>
              Use single-line command line editing instead of multi-line.

              Note  that  although  this  is  on  by  default  in  ksh  emulation  it  only provides superficial
              compatibility with the ksh line editor and reduces the effectiveness of the zsh line  editor.   As
              it  has  no  effect  on  shell  syntax,  many users may wish to disable this option when using ksh
              emulation interactively.

       VI     If ZLE is loaded, turning on this option has the equivalent effect of `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; bindkey is the recommended
              interface.

       ZLE (-Z)
              Use the zsh line editor.  Set by default in interactive shells connected to a terminal.

OPTION 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.

       BRACE_EXPAND
              NO_IGNORE_BRACES (ksh and bash compatibility)

       DOT_GLOB
              GLOB_DOTS (bash compatibility)

       HASH_ALL
              HASH_CMDS (bash compatibility)

       HIST_APPEND
              APPEND_HISTORY (bash compatibility)

       HIST_EXPAND
              BANG_HIST (bash compatibility)

       LOG    NO_HIST_NO_FUNCTIONS (ksh compatibility)

       MAIL_WARN
              MAIL_WARNING (bash compatibility)

       ONE_CMD
              SINGLE_COMMAND (bash compatibility)

       PHYSICAL
              CHASE_LINKS (ksh and bash compatibility)

       PROMPT_VARS
              PROMPT_SUBST (bash compatibility)

       STDIN  SHIN_STDIN (ksh compatibility)

       TRACK_ALL
              HASH_CMDS (ksh compatibility)

SINGLE LETTER OPTIONS

   Default set
       -0     CORRECT
       -1     PRINT_EXIT_VALUE
       -2     NO_BAD_PATTERN
       -3     NO_NOMATCH
       -4     GLOB_DOTS
       -5     NOTIFY
       -6     BG_NICE
       -7     IGNORE_EOF
       -8     MARK_DIRS
       -9     AUTO_LIST
       -B     NO_BEEP
       -C     NO_CLOBBER
       -D     PUSHD_TO_HOME
       -E     PUSHD_SILENT
       -F     NO_GLOB
       -G     NULL_GLOB
       -H     RM_STAR_SILENT
       -I     IGNORE_BRACES
       -J     AUTO_CD
       -K     NO_BANG_HIST
       -L     SUN_KEYBOARD_HACK
       -M     SINGLE_LINE_ZLE
       -N     AUTO_PUSHD
       -O     CORRECT_ALL
       -P     RC_EXPAND_PARAM
       -Q     PATH_DIRS
       -R     LONG_LIST_JOBS
       -S     REC_EXACT
       -T     CDABLE_VARS
       -U     MAIL_WARNING
       -V     NO_PROMPT_CR
       -W     AUTO_RESUME
       -X     LIST_TYPES
       -Y     MENU_COMPLETE
       -Z     ZLE
       -a     ALL_EXPORT
       -e     ERR_EXIT
       -f     NO_RCS
       -g     HIST_IGNORE_SPACE
       -h     HIST_IGNORE_DUPS
       -i     INTERACTIVE
       -k     INTERACTIVE_COMMENTS
       -l     LOGIN
       -m     MONITOR
       -n     NO_EXEC
       -p     PRIVILEGED
       -r     RESTRICTED
       -s     SHIN_STDIN
       -t     SINGLE_COMMAND
       -u     NO_UNSET
       -v     VERBOSE
       -w     CHASE_LINKS
       -x     XTRACE
       -y     SH_WORD_SPLIT

   sh/ksh emulation set
       -C     NO_CLOBBER
       -T     TRAPS_ASYNC
       -X     MARK_DIRS
       -a     ALL_EXPORT
       -b     NOTIFY
       -e     ERR_EXIT
       -f     NO_GLOB
       -i     INTERACTIVE
       -l     LOGIN
       -m     MONITOR
       -n     NO_EXEC
       -p     PRIVILEGED
       -r     RESTRICTED
       -s     SHIN_STDIN
       -t     SINGLE_COMMAND
       -u     NO_UNSET
       -v     VERBOSE
       -x     XTRACE

   Also note
       -A     Used by set for setting arrays
       -b     Used on the command line to specify end of option processing
       -c     Used on the command line to specify a single command
       -m     Used by setopt for pattern-matching option setting
       -o     Used in all places to allow use of long option names
       -s     Used by set to sort positional parameters