Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
ZSHEXPN(1)							    ZSHEXPN(1)

       zshexpn - zsh expansion and substitution

       The  following types of expansions are performed	in the indicated order
       in five steps:

       History Expansion
	      This is performed	only in	interactive shells.

       Alias Expansion
	      Aliases are expanded immediately	before	the  command  line  is
	      parsed as	explained under	Aliasing in zshmisc(1).

       Process Substitution
       Parameter Expansion
       Command Substitution
       Arithmetic Expansion
       Brace Expansion
	      These  five  are performed in one	step in	left-to-right fashion.
	      After these expansions, all unquoted occurrences of the  charac-
	      ters `\',	`'' and	`"' are	removed.

       Filename	Expansion
	      If  the  SH_FILE_EXPANSION option	is set,	the order of expansion
	      is modified for compatibility with sh and	 ksh.	In  that  case
	      filename	expansion  is performed	immediately after alias	expan-
	      sion, preceding the set of five expansions mentioned above.

       Filename	Generation
	      This expansion, commonly referred	to as globbing,	is always done

       The following sections explain the types	of expansion in	detail.

       History	expansion  allows you to use words from	previous command lines
       in the command line you are typing.  This simplifies  spelling  correc-
       tions and the repetition	of complicated commands	or arguments.

       Immediately  before  execution,	each  command  is saved	in the history
       list, the size of which is controlled by	the HISTSIZE  parameter.   The
       one  most  recent  command  is always retained in any case.  Each saved
       command in the history list is called a history event and is assigned a
       number,	beginning  with	1 (one)	when the shell starts up.  The history
       number that you may  see	 in  your  prompt  (see	 EXPANSION  OF	PROMPT
       SEQUENCES  in  zshmisc(1))  is the number that is to be assigned	to the
       next command.

       A history expansion begins with the first character  of	the  histchars
       parameter,  which is `!'	by default, and	may occur anywhere on the com-
       mand line; history expansions do	not nest.  The `!' can be escaped with
       `\' or can be enclosed between a	pair of	single quotes ('') to suppress
       its special meaning.  Double quotes will	not work for this.   Following
       this history character is an optional event designator (see the section
       `Event Designators') and	then an	optional word designator (the  section
       `Word  Designators');  if  neither  of these designators	is present, no
       history expansion occurs.

       Input lines  containing	history	 expansions  are  echoed  after	 being
       expanded,  but  before  any  other expansions take place	and before the
       command is executed.  It	is this	expanded form that is recorded as  the
       history event for later references.

       By  default, a history reference	with no	event designator refers	to the
       same event as any preceding history reference on	that command line;  if
       it  is the only history reference in a command, it refers to the	previ-
       ous command.  However, if the option CSH_JUNKIE_HISTORY	is  set,  then
       every  history  reference  with no event	specification always refers to
       the previous command.

       For example, `!'	is the event designator	for the	previous  command,  so
       `!!:1'  always  refers  to  the first word of the previous command, and
       `!!$' always refers to the last word of	the  previous  command.	  With
       CSH_JUNKIE_HISTORY set, then `!:1' and `!$' function in the same	manner
       as `!!:1' and `!!$', respectively.  Conversely,	if  CSH_JUNKIE_HISTORY
       is  unset,  then	 `!:1'	and  `!$'  refer  to the first and last	words,
       respectively, of	the same event referenced by the nearest other history
       reference  preceding them on the	current	command	line, or to the	previ-
       ous command if there is no preceding reference.

       The character sequence `^foo^bar' (where	`^'  is	 actually  the	second
       character of the	histchars parameter) repeats the last command, replac-
       ing the string foo with bar.  More precisely, the sequence  `^foo^bar^'
       is synonymous with `!!:s^foo^bar^', hence other modifiers (see the sec-
       tion  `Modifiers')  may	follow	the   final   `^'.    In   particular,
       `^foo^bar^:G' performs a	global substitution.

       If  the	shell encounters the character sequence	`!"' in	the input, the
       history mechanism is temporarily	disabled until the current  list  (see
       zshmisc(1))  is	fully parsed.  The `!"'	is removed from	the input, and
       any subsequent `!' characters have no special significance.

       A less convenient but more comprehensible form of command history  sup-
       port is provided	by the fc builtin.

   Event Designators
       An  event designator is a reference to a	command-line entry in the his-
       tory list.  In the list below, remember that the	initial	 `!'  in  each
       item  may  be  changed  to  another  character by setting the histchars

       !      Start a history expansion, except	when followed by a blank, new-
	      line,  `=' or `('.  If followed immediately by a word designator
	      (see the section `Word Designators'), this forms a history  ref-
	      erence with no event designator (see the section `Overview').

       !!     Refer  to	 the  previous	command.   By  itself,	this expansion
	      repeats the previous command.

       !n     Refer to command-line n.

       !-n    Refer to the current command-line	minus n.

       !str   Refer to the most	recent command starting	with str.

	      Refer to the most	recent command containing str.	 The  trailing
	      `?'  is necessary	if this	reference is to	be followed by a modi-
	      fier or followed by any text that	is not to be  considered  part
	      of str.

       !#     Refer  to	the current command line typed in so far.  The line is
	      treated as if it were complete up	 to  and  including  the  word
	      before the one with the `!#' reference.

       !{...} Insulate a history reference from	adjacent characters (if	neces-

   Word	Designators
       A word designator indicates which word or words of a given command line
       are to be included in a history reference.  A `:' usually separates the
       event specification from	the word designator.  It may be	 omitted  only
       if  the	word designator	begins with a `^', `$',	`*', `-' or `%'.  Word
       designators include:

       0      The first	input word (command).
       n      The nth argument.
       ^      The first	argument.  That	is, 1.
       $      The last argument.
       %      The word matched by (the most recent) ?str search.
       x-y    A	range of words;	x defaults to 0.
       *      All the arguments, or a null value if there are none.
       x*     Abbreviates `x-$'.
       x-     Like `x*'	but omitting word $.

       Note that a `%' word designator works only when used in	one  of	 `!%',
       `!:%'  or `!?str?:%', and only when used	after a	!? expansion (possibly
       in an earlier command).	Anything else results in  an  error,  although
       the error may not be the	most obvious one.

       After  the  optional  word designator, you can add a sequence of	one or
       more of the following modifiers,	each preceded by a `:'.	  These	 modi-
       fiers  also  work  on  the  result of filename generation and parameter
       expansion, except where noted.

       a      Turn a file name into an absolute	path:	prepends  the  current
	      directory,  if  necessary;  remove `.' path segments; and	remove
	      `..' path	segments and the  segments  that  immediately  precede

	      This transformation is agnostic about what is in the filesystem,
	      i.e. is on the logical, not the physical	directory.   It	 takes
	      place  in	the same manner	as when	changing directories when nei-
	      ther of the options CHASE_DOTS or	CHASE_LINKS is set.  For exam-
	      ple,    `/before/here/../after'	is   always   transformed   to
	      `/before/after', regardless of whether `/before/here' exists  or
	      what kind	of object (dir,	file, symlink, etc.) it	is.

       A      Turn a file name into an absolute	path as	the `a'	modifier does,
	      and then pass the	result through the realpath(3)	library	 func-
	      tion to resolve symbolic links.

	      Note:  on	 systems  that do not have a realpath(3) library func-
	      tion, symbolic links are not resolved, so	on those  systems  `a'
	      and `A' are equivalent.

	      Note: foo:A and realpath(foo) are	different on some inputs.  For
	      realpath(foo) semantics, see the `P` modifier.

       c      Resolve a	command	name into an absolute path  by	searching  the
	      command path given by the	PATH variable.	This does not work for
	      commands containing directory parts.  Note also that  this  does
	      not  usually  work as a glob qualifier unless a file of the same
	      name is found in the current directory.

       e      Remove all but the part of the filename extension	following  the
	      `.';  see	 the  definition  of  the  filename  extension	in the
	      description of the r modifier below.   Note  that	 according  to
	      that definition the result will be empty if the string ends with
	      a	`.'.

       h      Remove a trailing	pathname component, leaving  the  head.	  This
	      works like `dirname'.

       l      Convert the words	to all lowercase.

       p      Print  the  new  command but do not execute it.  Only works with
	      history expansion.

       P      Turn a file name into an absolute	path, like  realpath(3).   The
	      resulting	 path will be absolute,	have neither `.' nor `..' com-
	      ponents, and refer to the	same  directory	 entry	as  the	 input

	      Unlike realpath(3), non-existent trailing	components are permit-
	      ted and preserved.

       q      Quote the	substituted  words,  escaping  further	substitutions.
	      Works with history expansion and parameter expansion, though for
	      parameters it is only useful if the  resulting  text  is	to  be
	      re-evaluated such	as by eval.

       Q      Remove one level of quotes from the substituted words.

       r      Remove a filename	extension leaving the root name.  Strings with
	      no filename extension are	not altered.  A	filename extension  is
	      a	`.' followed by	any number of characters (including zero) that
	      are neither `.' nor `/' and that continue	 to  the  end  of  the
	      string.  For example, the	extension of `foo.orig.c' is `.c', and
	      `dir.c/foo' has no extension.

	      Substitute r for l as described below.  The substitution is done
	      only  for	 the  first string that	matches	l.  For	arrays and for
	      filename generation, this	applies	to each	word of	 the  expanded
	      text.  See below for further notes on substitutions.

	      The  forms  `gs/l/r' and `s/l/r/:G' perform global substitution,
	      i.e. substitute every occurrence of r for	l.  Note that the g or
	      :G must appear in	exactly	the position shown.

	      See further notes	on this	form of	substitution below.

       &      Repeat  the  previous  s	substitution.  Like s, may be preceded
	      immediately by a g.  In parameter	expansion the  &  must	appear
	      inside braces, and in filename generation	it must	be quoted with
	      a	backslash.

       t      Remove all leading pathname components, leaving the tail.	  This
	      works like `basename'.

       u      Convert the words	to all uppercase.

       x      Like  q, but break into words at whitespace.  Does not work with
	      parameter	expansion.

       The s/l/r/ substitution works as	follows.   By  default	the  left-hand
       side  of	 substitutions	are  not patterns, but character strings.  Any
       character can be	used as	the delimiter in place of  `/'.	  A  backslash
       quotes	the   delimiter	  character.	The   character	 `&',  in  the
       right-hand-side r, is replaced by the text from the  left-hand-side  l.
       The  `&'	 can  be  quoted with a	backslash.  A null l uses the previous
       string either from the previous l or from the contextual	scan string  s
       from  `!?s'.  You can omit the rightmost	delimiter if a newline immedi-
       ately follows r;	the rightmost `?' in a context scan can	 similarly  be
       omitted.	 Note the same record of the last l and	r is maintained	across
       all forms of expansion.

       Note that if a `&' is used within glob qualifiers an extra backslash is
       needed as a & is	a special character in this case.

       Also  note that the order of expansions affects the interpretation of l
       and r.  When used in a history expansion, which occurs before any other
       expansions, l and r are treated as literal strings (except as explained
       for HIST_SUBST_PATTERN below).  When used in parameter  expansion,  the
       replacement of r	into the parameter's value is done first, and then any
       additional process, parameter, command, arithmetic, or brace references
       are applied, which may evaluate those substitutions and expansions more
       than once if l appears more than	once in	the starting value.  When used
       in a glob qualifier, any	substitutions or expansions are	performed once
       at the time the qualifier is parsed, even before	 the  `:s'  expression
       itself is divided into l	and r sides.

       If  the	option HIST_SUBST_PATTERN is set, l is treated as a pattern of
       the usual form described	in  the	 section  FILENAME  GENERATION	below.
       This can	be used	in all the places where	modifiers are available; note,
       however,	that in	globbing qualifiers parameter substitution has already
       taken  place,  so parameters in the replacement string should be	quoted
       to ensure they are replaced at the correct time.	 Note also  that  com-
       plicated	 patterns  used	 in  globbing qualifiers may need the extended
       glob qualifier notation (#q:s/.../.../) in order	for the	shell to  rec-
       ognize the expression as	a glob qualifier.  Further, note that bad pat-
       terns in	the substitution are not subject to the	NO_BAD_PATTERN	option
       so will cause an	error.

       When  HIST_SUBST_PATTERN	 is set, l may start with a # to indicate that
       the pattern must	match at the start of the string  to  be  substituted,
       and a % may appear at the start or after	an # to	indicate that the pat-
       tern must match at the end of the string	to be substituted.  The	% or #
       may be quoted with two backslashes.

       For  example,  the following piece of filename generation code with the
       EXTENDED_GLOB option:

	      print *.c(#q:s/#%(#b)s(*).c/'S${match[1]}.C'/)

       takes the expansion of *.c and  applies	the  glob  qualifiers  in  the
       (#q...)	expression, which consists of a	substitution modifier anchored
       to the start and	end of each word (#%).	This turns  on	backreferences
       ((#b)),	so  that  the  parenthesised subexpression is available	in the
       replacement string as ${match[1]}.  The replacement string is quoted so
       that the	parameter is not substituted before the	start of filename gen-

       The following f,	F, w and W modifiers work only with  parameter	expan-
       sion and	filename generation.  They are listed here to provide a	single
       point of	reference for all modifiers.

       f      Repeats the immediately (without	a  colon)  following  modifier
	      until the	resulting word doesn't change any more.

	      Like  f,	but repeats only n times if the	expression expr	evalu-
	      ates to n.  Any character	can be used instead  of	 the  `:';  if
	      `(',  `[',  or `{' is used as the	opening	delimiter, the closing
	      delimiter	should be ')', `]', or `}', respectively.

       w      Makes the	immediately following modifier work on	each  word  in
	      the string.

       W:sep: Like  w  but  words are considered to be the parts of the	string
	      that are separated by sep. Any character can be used instead  of
	      the `:'; opening parentheses are handled specially, see above.

       Each  part  of  a  command  argument  that  takes  the  form `<(list)',
       `>(list)' or `=(list)' is subject to process substitution.  The expres-
       sion  may be preceded or	followed by other strings except that, to pre-
       vent clashes with commonly occurring strings  and  patterns,  the  last
       form  must  occur at the	start of a command argument, and the forms are
       only expanded when  first  parsing  command  or	assignment  arguments.
       Process	substitutions  may be used following redirection operators; in
       this case, the substitution must	appear with no trailing	string.

       Note that `<<(list)' is not a special syntax; it	is  equivalent	to  `<
       <(list)', redirecting standard input from the result of process substi-
       tution.	Hence all the following	 documentation	applies.   The	second
       form (with the space) is	recommended for	clarity.

       In the case of the < or > forms,	the shell runs the commands in list as
       a subprocess of the job executing the shell command line.  If the  sys-
       tem supports the	/dev/fd	mechanism, the command argument	is the name of
       the device file corresponding to	a file descriptor; otherwise,  if  the
       system  supports	 named	pipes  (FIFOs),	the command argument will be a
       named pipe.  If the form	with > is selected then	writing	on  this  spe-
       cial  file  will	 provide  input	for list.  If <	is used, then the file
       passed as an argument will be connected	to  the	 output	 of  the  list
       process.	 For example,

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

       cuts fields 1 and 3 from	the files file1	and file2 respectively,	pastes
       the results together, and  sends	 it  to	 the  processes	 process1  and

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

       There is	an optimisation	for substitutions of the form =(<<<arg), where
       arg is a	single-word argument to	the here-string	redirection <<<.  This
       form produces a file name containing the	value of arg after any substi-
       tutions	have been performed.  This is handled entirely within the cur-
       rent shell.  This is  effectively  the  reverse	of  the	 special  form
       $(<arg) which treats arg	as a file name and replaces it with the	file's

       The = form is useful as both the	/dev/fd	and the	named pipe implementa-
       tion of <(...) have drawbacks.  In the former case, some	programmes may
       automatically close the file descriptor in  question  before  examining
       the  file  on  the  command line, particularly if this is necessary for
       security	reasons	such as	when the programme is running setuid.  In  the
       second case, if the programme does not actually open the	file, the sub-
       shell attempting	to read	from or	write to the pipe will (in  a  typical
       implementation,	different  operating systems may have different	behav-
       iour) block for ever and	have to	be killed explicitly.  In both	cases,
       the  shell actually supplies the	information using a pipe, so that pro-
       grammes that expect to lseek (see lseek(2)) on the file will not	 work.

       Also  note  that	 the  previous example can be more compactly and effi-
       ciently written (provided the MULTIOS option is set) as:

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

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

       There  is  an additional	problem	with >(process); when this is attached
       to an external command, the parent shell	does not wait for  process  to
       finish  and  hence  an immediately following command cannot rely	on the
       results being complete.	The problem  and  solution  are	 the  same  as
       described  in the section MULTIOS in zshmisc(1).	 Hence in a simplified
       version of the example above:

	      paste <(cut -f1 file1) <(cut -f3 file2) >	>(process)

       (note that no MULTIOS are involved), process will be run	asynchronously
       as far as the parent shell is concerned.	 The workaround	is:

	      {	paste <(cut -f1	file1) <(cut -f3 file2)	} > >(process)

       The  extra  processes here are spawned from the parent shell which will
       wait for	their completion.

       Another problem arises any time a job with a substitution that requires
       a  temporary  file  is  disowned	by the shell, including	the case where
       `&!' or `&|' appears at the end of a command containing a substitution.
       In  that	case the temporary file	will not be cleaned up as the shell no
       longer has any memory of	the job.  A workaround is to use  a  subshell,
       for example,

	      (mycmd =(myoutput)) &!

       as  the forked subshell will wait for the command to finish then	remove
       the temporary file.

       A general workaround to ensure a	process	substitution  endures  for  an
       appropriate length of time is to	pass it	as a parameter to an anonymous
       shell function (a piece of shell	code  that  is	run  immediately  with
       function	scope).	 For example, this code:

	      () {
		 print File $1:
		 cat $1
	      }	=(print	This be	the verse)

       outputs something resembling the	following

	      File /tmp/zsh6nU0kS:
	      This be the verse

       The  temporary file created by the process substitution will be deleted
       when the	function exits.

       The character `$' is used to introduce parameter	expansions.  See  zsh-
       param(1)	for a description of parameters, including arrays, associative
       arrays, and subscript notation to access	individual array elements.

       Note in particular the fact that	words of unquoted parameters  are  not
       automatically  split  on	 whitespace unless the option SH_WORD_SPLIT is
       set; see	references to this option below	for more details.  This	is  an
       important difference from other shells.

       In  the	expansions discussed below that	require	a pattern, the form of
       the pattern is the same as that used for	filename generation;  see  the
       section	`Filename  Generation'.	  Note that these patterns, along with
       the replacement text of any substitutions, are  themselves  subject  to
       parameter  expansion,  command  substitution, and arithmetic expansion.
       In addition to the following operations,	the colon modifiers  described
       in  the	section	 `Modifiers' in	the section `History Expansion'	can be
       applied:	 for example, ${i:s/foo/bar/} performs string substitution  on
       the expansion of	parameter $i.

       In  the	following descriptions,	`word' refers to a single word substi-
       tuted on	the command line, not  necessarily  a  space  delimited	 word.
       With default options, after the assignments:

	      array=("first word" "second word")
	      scalar="only word"

       then  $array substitutes	two words, `first word'	and `second word', and
       $scalar substitutes a single word `only word'.  This may	be modified by
       explicit	 or implicit word-splitting, however.  The full	rules are com-
       plicated	and are	noted at the end.

	      The value, if any, of the	parameter name	is  substituted.   The
	      braces are required if the expansion is to be followed by	a let-
	      ter, digit, or underscore	that is	not to be interpreted as  part
	      of  name.	  In  addition,	more complicated forms of substitution
	      usually require the braces to be present;	exceptions, which only
	      apply  if	 the  option  KSH_ARRAYS is not	set, are a single sub-
	      script or	any colon modifiers appearing after the	name,  or  any
	      of the characters	`^', `=', `~', `#' or `+' appearing before the
	      name, all	of which work with or without braces.

	      If name is an array parameter, and the KSH_ARRAYS	option is  not
	      set,  then the value of each element of name is substituted, one
	      element per word.	 Otherwise, the	expansion results in one  word
	      only;  with  KSH_ARRAYS,	this is	the first element of an	array.
	      No  field	 splitting  is	done  on   the	 result	  unless   the
	      SH_WORD_SPLIT   option  is  set.	 See  also  the	 flags	=  and

	      If name is the name of a set parameter `1' is substituted,  oth-
	      erwise `0' is substituted.

	      If  name is set, or in the second	form is	non-null, then substi-
	      tute its value; otherwise	substitute word.  In the  second  form
	      name may be omitted, in which case word is always	substituted.

	      If  name is set, or in the second	form is	non-null, then substi-
	      tute word; otherwise substitute nothing.

	      In the first form, if name is unset then set it to word; in  the
	      second  form,  if	name is	unset or null then set it to word; and
	      in the third form, unconditionally set name  to  word.   In  all
	      forms, the value of the parameter	is then	substituted.

	      In the first form, if name is set, or in the second form if name
	      is both set and non-null,	then substitute	its value;  otherwise,
	      print  word and exit from	the shell.  Interactive	shells instead
	      return to	the prompt.  If	word is	omitted, then a	standard  mes-
	      sage is printed.

       In  any of the above expressions	that test a variable and substitute an
       alternate word, note that you can use standard  shell  quoting  in  the
       word   value   to  selectively  override	 the  splitting	 done  by  the
       SH_WORD_SPLIT option and	the = flag, but	not splitting by the s:string:

       In  the	following expressions, when name is an array and the substitu-
       tion is not quoted, or if the `(@)' flag	or the name[@] syntax is used,
       matching	and replacement	is performed on	each array element separately.

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

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

	      If the pattern matches the value of name,	 then  substitute  the
	      empty  string; otherwise,	just substitute	the value of name.  If
	      name is an array the matching array elements  are	 removed  (use
	      the `(M)'	flag to	remove the non-matched elements).

	      If  arrayname is the name	(N.B., not contents) of	an array vari-
	      able, then any elements contained	in arrayname are removed  from
	      the substitution of name.	 If the	substitution is	scalar,	either
	      because name is a	scalar variable	or the expression  is  quoted,
	      the  elements of arrayname are instead tested against the	entire

	      Similar to the  preceding	 substitution,	but  in	 the  opposite
	      sense, so	that entries present in	both the original substitution
	      and as elements of arrayname are retained	and others removed.

	      Zips two arrays, such that the output array is twice as long  as
	      the shortest (longest for	`:^^') of name and arrayname, with the
	      elements alternatingly being picked from them. For `:^', if  one
	      of the input arrays is longer, the output	will stop when the end
	      of the shorter array is reached.	Thus,

		     a=(1 2 3 4); b=(a b); print ${a:^b}

	      will output `1 a 2 b'.  For `:^^', then the  input  is  repeated
	      until  all  of  the  longer array	has been used up and the above
	      will output `1 a 2 b 3 a 4 b'.

	      Either or	both inputs may	be a scalar, they will be  treated  as
	      an  array	 of  length  1 with the	scalar as the only element. If
	      either array is empty, the other array is	output with  no	 extra
	      elements inserted.

	      Currently	 the  following	 code will output `a b'	and `1'	as two
	      separate elements, which can be  unexpected.  The	 second	 print
	      provides	a  workaround which should continue to work if this is

		     a=(a b); b=(1 2); print -l	"${a:^b}"; print -l "${${a:^b}}"

	      This syntax gives	effects	similar	to parameter  subscripting  in
	      the  form	$name[start,end], but is compatible with other shells;
	      note that	both offset and	 length	 are  interpreted  differently
	      from the components of a subscript.

	      If offset	is non-negative, then if the variable name is a	scalar
	      substitute the contents  starting	 offset	 characters  from  the
	      first  character	of the string, and if name is an array substi-
	      tute elements starting offset elements from the  first  element.
	      If length	is given, substitute that many characters or elements,
	      otherwise	the entire rest	of the scalar or array.

	      A	positive offset	is always treated as the offset	of a character
	      or  element  in  name from the first character or	element	of the
	      array (this is different from native  zsh	 subscript  notation).
	      Hence  0	refers to the first character or element regardless of
	      the setting of the option	KSH_ARRAYS.

	      A	negative offset	counts backwards from the end of the scalar or
	      array,  so that -1 corresponds to	the last character or element,
	      and so on.

	      When positive, length counts from	the offset position toward the
	      end  of  the scalar or array.  When negative, length counts back
	      from the end.  If	this results in	a position smaller  than  off-
	      set, a diagnostic	is printed and nothing is substituted.

	      The option MULTIBYTE is obeyed, i.e. the offset and length count
	      multibyte	characters where appropriate.

	      offset and length	undergo	the same set of	shell substitutions as
	      for  scalar  assignment;	in  addition, they are then subject to
	      arithmetic evaluation.  Hence, for example

		     print ${foo:3}
		     print ${foo: 1 + 2}
		     print ${foo:$(( 1 + 2))}
		     print ${foo:$(echo	1 + 2)}

	      all have the same	effect,	extracting the string starting at  the
	      fourth  character	 of  $foo  if the substitution would otherwise
	      return a scalar, or the array starting at	the fourth element  if
	      $foo   would  return  an	array.	 Note  that  with  the	option
	      KSH_ARRAYS $foo always returns a scalar (regardless of  the  use
	      of the offset syntax) and	a form such as ${foo[*]:3} is required
	      to extract elements of an	array named foo.

	      If offset	is negative, the - may not  appear  immediately	 after
	      the  : as	this indicates the ${name:-word} form of substitution.
	      Instead, a space may be inserted	before	the  -.	  Furthermore,
	      neither offset nor length	may begin with an alphabetic character
	      or & as these are	used to	indicate history-style modifiers.   To
	      substitute  a value from a variable, the recommended approach is
	      to precede it with a $ as	this signifies the intention  (parame-
	      ter substitution can easily be rendered unreadable); however, as
	      arithmetic substitution  is  performed,  the  expression	${var:
	      offs} does work, retrieving the offset from $offs.

	      For  further  compatibility with other shells there is a special
	      case for array offset 0.	This usually accesses the  first  ele-
	      ment  of	the array.  However, if	the substitution refers	to the
	      positional parameter array, e.g. $@ or $*, then offset 0 instead
	      refers to	$0, offset 1 refers to $1, and so on.  In other	words,
	      the  positional  parameter  array	 is  effectively  extended  by
	      prepending  $0.  Hence ${*:0:1} substitutes $0 and ${*:1:1} sub-
	      stitutes $1.

	      Replace the longest possible match of pattern in	the  expansion
	      of  parameter name by string repl.  The first form replaces just
	      the first	occurrence, the	second form all	occurrences,  and  the
	      third  form  replaces only if pattern matches the	entire string.
	      Both pattern and repl are	subject	to double-quoted substitution,
	      so that expressions like ${name/$opat/$npat} will	work, but obey
	      the usual	rule that pattern characters in	$opat are not  treated
	      specially	 unless	 either	the option GLOB_SUBST is set, or $opat
	      is instead substituted as	${~opat}.

	      The pattern may begin with a `#',	in which case the pattern must
	      match  at	the start of the string, or `%', in which case it must
	      match at the end of the string, or `#%' in which case  the  pat-
	      tern  must  match	 the  entire string.  The repl may be an empty
	      string, in which case the	final `/' may  also  be	 omitted.   To
	      quote  the  final	 `/' in	other cases it should be preceded by a
	      single backslash;	this is	not necessary if the `/' occurs	inside
	      a	 substituted  parameter.   Note	also that the `#', `%' and `#%
	      are not active if	they occur  inside  a  substituted  parameter,
	      even at the start.

	      If,  after quoting rules apply, ${name} expands to an array, the
	      replacements act on each element individually.   Note  also  the
	      effect  of the I and S parameter expansion flags below; however,
	      the flags	M, R, B, E and N are not useful.

	      For example,

		     foo="twinkle twinkle little star" sub="t*e" rep="spy"
		     print ${foo//${~sub}/$rep}
		     print ${(S)foo//${~sub}/$rep}

	      Here, the	`~' ensures that the text of $sub is treated as	a pat-
	      tern rather than a plain string.	In the first case, the longest
	      match for	t*e is substituted and the result is `spy star', while
	      in  the  second  case,  the  shortest  matches are taken and the
	      result is	`spy spy lispy star'.

	      If spec is one of	the above substitutions, substitute the	length
	      in  characters  of  the result instead of	the result itself.  If
	      spec is an array expression, substitute the number  of  elements
	      of the result.  This has the side-effect that joining is skipped
	      even in quoted forms, which may affect other sub-expressions  in
	      spec.   Note  that  `^', `=', and	`~', below, must appear	to the
	      left of `#' when these forms are combined.

	      If the option POSIX_IDENTIFIERS is not set, and spec is a	simple
	      name,  then  the braces are optional; this is true even for spe-
	      cial parameters so e.g. $#- and  $#*  take  the  length  of  the
	      string  $-  and the array	$* respectively.  If POSIX_IDENTIFIERS
	      is set, then braces are required for the # to be treated in this

	      Turn  on	the RC_EXPAND_PARAM option for the evaluation of spec;
	      if the `^' is doubled, turn it off.  When	this  option  is  set,
	      array expansions of the form foo${xx}bar,	where the parameter xx
	      is set to	 (a  b	c),  are  substituted  with  `fooabar  foobbar
	      foocbar'	instead	 of  the  default `fooa	b cbar'.  Note that an
	      empty array will therefore cause all arguments to	be removed.

	      Internally, each such expansion is converted into	the equivalent
	      list    for    brace    expansion.     E.g.,   ${^var}   becomes
	      {$var[1],$var[2],...}, and is processed as described in the sec-
	      tion  `Brace  Expansion'	below.	 If  word splitting is also in
	      effect the $var[N] may themselves	be split into  different  list

	      Perform  word splitting using the	rules for SH_WORD_SPLIT	during
	      the evaluation of	spec, but regardless of	whether	the  parameter
	      appears  in  double  quotes; if the `=' is doubled, turn it off.
	      This forces parameter expansions to be split into	separate words
	      before  substitution, using IFS as a delimiter.  This is done by
	      default in most other shells.

	      Note that	splitting is applied to	word in	the  assignment	 forms
	      of  spec	before	the  assignment	 to  name  is performed.  This
	      affects the result of array assignments with the A flag.

	      Turn on the GLOB_SUBST option for	the evaluation of spec;	if the
	      `~'  is  doubled,	 turn  it  off.	  When this option is set, the
	      string resulting from the	expansion will	be  interpreted	 as  a
	      pattern anywhere that is possible, such as in filename expansion
	      and filename generation and pattern-matching contexts  like  the
	      right hand side of the `=' and `!=' operators in conditions.

	      In  nested  substitutions, note that the effect of the ~ applies
	      to the result of the current level of substitution.  A surround-
	      ing  pattern  operation on the result may	cancel it.  Hence, for
	      example, if the parameter	foo is set to  *,  ${~foo//\*/*.c}  is
	      substituted  by  the pattern *.c,	which may be expanded by file-
	      name  generation,	 but  ${${~foo}//\*/*.c}  substitutes  to  the
	      string *.c, which	will not be further expanded.

       If  a ${...} type parameter expression or a $(...) type command substi-
       tution is used in place of name above, it is  expanded  first  and  the
       result is used as if it were the	value of name.	Thus it	is possible to
       perform nested operations:  ${${foo#head}%tail} substitutes  the	 value
       of  $foo	 with both `head' and `tail' deleted.  The form	with $(...) is
       often useful in combination with	the  flags  described  next;  see  the
       examples	 below.	  Each	name or	nested ${...} in a parameter expansion
       may also	be followed by a subscript expression as  described  in	 Array
       Parameters in zshparam(1).

       Note  that double quotes	may appear around nested expressions, in which
       case  only  the	part  inside  is  treated  as  quoted;	for   example,
       ${(f)"$(foo)"}  quotes  the  result  of $(foo), but the flag `(f)' (see
       below) is applied using the rules for unquoted expansions.   Note  fur-
       ther that quotes	are themselves nested in this context; for example, in
       "${(@f)"$(foo)"}", there	are two	sets of	quotes,	 one  surrounding  the
       whole  expression,  the	other  (redundant)  surrounding	 the $(foo) as

   Parameter Expansion Flags
       If the opening brace is directly	followed by  an	 opening  parenthesis,
       the  string  up	to the matching	closing	parenthesis will be taken as a
       list of flags.  In cases	where repeating	a flag is meaningful, the rep-
       etitions	need not be consecutive; for example, `(q%q%q)'	means the same
       thing as	the more readable `(%%qqq)'.  The  following  flags  are  sup-

       #      Evaluate	the  resulting words as	numeric	expressions and	output
	      the characters corresponding to  the  resulting  integer.	  Note
	      that  this  form	is entirely distinct from use of the # without

	      If the MULTIBYTE option is set and the number  is	 greater  than
	      127  (i.e.  not  an  ASCII character) it is treated as a Unicode

       %      Expand all % escapes in the resulting words in the same  way  as
	      in prompts (see EXPANSION	OF PROMPT SEQUENCES in zshmisc(1)). If
	      this flag	is given twice,	full prompt expansion is done  on  the
	      resulting	words, depending on the	setting	of the PROMPT_PERCENT,
	      PROMPT_SUBST and PROMPT_BANG options.

       @      In double	quotes,	array elements are put	into  separate	words.
	      E.g.,   `"${(@)foo}"'   is   equivalent	to  `"${foo[@]}"'  and
	      `"${(@)foo[1,2]}"' is the	same as	`"$foo[1]"  "$foo[2]"'.	  This
	      is  distinct  from field splitting by the	f, s or	z flags, which
	      still applies within each	array element.

       A      Create an	array parameter	with  `${...=...}',  `${...:=...}'  or
	      `${...::=...}'.	If  this flag is repeated (as in `AA'),	create
	      an associative array parameter.  Assignment is made before sort-
	      ing  or  padding;	if field splitting is active, the word part is
	      split before assignment.	The name part  may  be	a  subscripted
	      range for	ordinary arrays; the word part must be converted to an
	      array, for example by using `${(AA)=name=...}' to	activate field
	      splitting, when creating an associative array.

       a      Sort  in	array  index  order;  when  combined  with `O' sort in
	      reverse array index order.  Note that `a'	is  therefore  equiva-
	      lent  to the default but `Oa' is useful for obtaining an array's
	      elements in reverse order.

       b      Quote with backslashes only characters that are special to  pat-
	      tern  matching. This is useful when the contents of the variable
	      are to be	tested using GLOB_SUBST, including the ${~...} switch.

	      Quoting  using  one  of  the q family of flags does not work for
	      this purpose since quotes	 are  not  stripped  from  non-pattern
	      characters by GLOB_SUBST.	 In other words,

		     [[	$str = ${~pattern} ]]

	      works if $str is `a*b' but not if	it is `a b', whereas

		     [[	$str = ${~pattern} ]]

	      is always	true for any possible value of $str.

       c      With ${#name}, count the total number of characters in an	array,
	      as if the	elements were concatenated with	spaces	between	 them.
	      This  is not a true join of the array, so	other expressions used
	      with this	flag may have an effect	on the elements	of  the	 array
	      before it	is counted.

       C      Capitalize  the resulting	words.	`Words'	in this	case refers to
	      sequences	of alphanumeric	characters separated  by  non-alphanu-
	      merics, not to words that	result from field splitting.

       D      Assume  the  string  or  array  elements contain directories and
	      attempt to substitute the	leading	part of	these by  names.   The
	      remainder	 of  the path (the whole of it if the leading part was
	      not substituted) is then quoted so that the whole	string can  be
	      used  as a shell argument.  This is the reverse of `~' substitu-
	      tion:  see the section FILENAME EXPANSION	below.

       e      Perform parameter	expansion, command substitution	and arithmetic
	      expansion	 on  the result. Such expansions can be	nested but too
	      deep recursion may have unpredictable effects.

       f      Split the	result of the expansion	at newlines. This is a	short-
	      hand for `ps:\n:'.

       F      Join  the	words of arrays	together using newline as a separator.
	      This is a	shorthand for `pj:\n:'.

	      Process escape sequences like the	echo builtin when  no  options
	      are  given (g::).	 With the o option, octal escapes don't	take a
	      leading zero.  With the c	option,	sequences like `^X'  are  also
	      processed.   With	 the  e	 option,  processes `\M-t' and similar
	      sequences	like the print builtin.	 With both  of	the  o	and  e
	      options,	behaves	 like the print	builtin	except that in none of
	      these modes is `\c' interpreted.

       i      Sort case-insensitively.	May be combined	with `n' or `O'.

       k      If name refers to	an  associative	 array,	 substitute  the  keys
	      (element	names)	rather	than the values	of the elements.  Used
	      with subscripts (including ordinary arrays),  force  indices  or
	      keys to be substituted even if the subscript form	refers to val-
	      ues.  However, this flag may  not	 be  combined  with  subscript

       L      Convert all letters in the result	to lower case.

       n      Sort  decimal integers numerically; if the first differing char-
	      acters of	two test strings are not digits, sorting  is  lexical.
	      Integers	with  more initial zeroes are sorted before those with
	      fewer or none.  Hence the	array  `foo1  foo02  foo2  foo3	 foo20
	      foo23' is	sorted into the	order shown.  May be combined with `i'
	      or `O'.

       o      Sort the resulting words in ascending order; if this appears  on
	      its  own	the  sorting is	lexical	and case-sensitive (unless the
	      locale renders it	case-insensitive).  Sorting in ascending order
	      is the default for other forms of	sorting, so this is ignored if
	      combined with `a', `i' or	`n'.

       O      Sort the resulting words in descending order; `O'	 without  `a',
	      `i' or `n' sorts in reverse lexical order.  May be combined with
	      `a', `i' or `n' to reverse the order of sorting.

       P      This forces the value of the parameter name to be	interpreted as
	      a	 further parameter name, whose value will be used where	appro-
	      priate.  Note that flags set with	one of the typeset  family  of
	      commands (in particular case transformations) are	not applied to
	      the value	of name	used in	this fashion.

	      If used with a nested parameter  or  command  substitution,  the
	      result  of  that	will  be taken as a parameter name in the same
	      way.  For	example, if you	 have  `foo=bar'  and  `bar=baz',  the
	      strings  ${(P)foo},  ${(P)${foo}}, and ${(P)$(echo bar)} will be
	      expanded to `baz'.

	      Likewise,	if the reference is itself nested, the expression with
	      the  flag	 is  treated  as  if  it were directly replaced	by the
	      parameter	name.  It is an	error if this nested substitution pro-
	      duces  an	 array	with  more  than  one  word.   For example, if
	      `name=assoc' where the parameter assoc is	an associative	array,
	      then  `${${(P)name}[elt]}' refers	to the element of the associa-
	      tive subscripted `elt'.

       q      Quote characters that are	special	to the shell in	the  resulting
	      words  with  backslashes;	 unprintable or	invalid	characters are
	      quoted using the $'\NNN' form, with  separate  quotes  for  each

	      If  this	flag is	given twice, the resulting words are quoted in
	      single quotes and	if it is given	three  times,  the  words  are
	      quoted  in  double quotes; in these forms	no special handling of
	      unprintable or invalid characters	is attempted.  If the flag  is
	      given four times,	the words are quoted in	single quotes preceded
	      by a $.  Note that in all	three of these forms quoting  is  done
	      unconditionally,	even  if  this	does  not  change  the way the
	      resulting	string would be	interpreted by the shell.

	      If a q- is given (only a single q	may appear), a minimal form of
	      single  quoting is used that only	quotes the string if needed to
	      protect special characters.  Typically this form gives the  most
	      readable output.

	      If  a  q+	 is  given, an extended	form of	minmal quoting is used
	      that causes unprintable characters to be rendered	using  $'...'.
	      This  quoting is similar to that used by the output of values by
	      the typeset family of commands.

       Q      Remove one level of quotes from the resulting words.

       t      Use a string describing the type	of  the	 parameter  where  the
	      value  of	 the  parameter	would usually appear. This string con-
	      sists of keywords	separated by hyphens (`-'). The	first  keyword
	      in  the  string  describes  the  main  type,  it	can  be	one of
	      `scalar',	`array',  `integer',  `float'  or  `association'.  The
	      other keywords describe the type in more detail:

	      local  for local parameters

	      left   for left justified	parameters

		     for right justified parameters with leading blanks

		     for right justified parameters with leading zeros

	      lower  for parameters whose value	is converted to	all lower case
		     when it is	expanded

	      upper  for parameters whose value	is converted to	all upper case
		     when it is	expanded

		     for readonly parameters

	      tag    for tagged	parameters

	      export for exported parameters

	      unique for arrays	which keep only	the first occurrence of	dupli-
		     cated values

	      hide   for parameters with the `hide' flag

		     for parameters with the `hideval' flag

		     for special parameters defined by the shell

       u      Expand only the first occurrence of each unique word.

       U      Convert all letters in the result	to upper case.

       v      Used with	k, substitute (as two consecutive words) both the  key
	      and the value of each associative	array element.	Used with sub-
	      scripts, force values to be substituted even  if	the  subscript
	      form refers to indices or	keys.

       V      Make any special characters in the resulting words visible.

       w      With  ${#name}, count words in arrays or strings;	the s flag may
	      be used to set a word delimiter.

       W      Similar to w  with  the  difference  that	 empty	words  between
	      repeated delimiters are also counted.

       X      With  this  flag,	 parsing  errors occurring with	the Q, e and #
	      flags or the pattern matching forms  such	 as  `${name#pattern}'
	      are reported.  Without the flag, errors are silently ignored.

       z      Split the	result of the expansion	into words using shell parsing
	      to find the words, i.e. taking into account any quoting  in  the
	      value.   Comments	 are  not  treated  specially  but as ordinary
	      strings, similar to interactive shells with the INTERACTIVE_COM-
	      MENTS  option  unset  (however, see the Z	flag below for related

	      Note that	this is	done very late,	 even  later  than  the	 `(s)'
	      flag.  So	to access single words in the result use nested	expan-
	      sions as in `${${(z)foo}[2]}'. Likewise, to remove the quotes in
	      the resulting words use `${(Q)${(z)foo}}'.

       0      Split  the  result  of  the  expansion on	null bytes.  This is a
	      shorthand	for `ps:\0:'.

       The following flags (except p) are followed by one or more arguments as
       shown.  Any character, or the matching pairs `(...)', `{...}', `[...]',
       or `<...>', may be used in place	of a colon  as	delimiters,  but  note
       that when a flag	takes more than	one argument, a	matched	pair of	delim-
       iters must surround each	argument.

       p      Recognize	the same escape	sequences  as  the  print  builtin  in
	      string arguments to any of the flags described below that	follow
	      this argument.

	      Alternatively, with this option string arguments may be  in  the
	      form  $var  in  which  case the value of the variable is substi-
	      tuted.  Note this	form is	strict;	the string argument  does  not
	      undergo general parameter	expansion.

	      For example,

		     print ${(ps.$sep.)val}

	      splits the variable on a :.

       ~      Strings  inserted	 into  the expansion by	any of the flags below
	      are to be	treated	as patterns.  This applies to the string argu-
	      ments of flags that follow ~ within the same set of parentheses.
	      Compare with ~ outside parentheses, which	forces the entire sub-
	      stituted string to be treated as a pattern.  Hence, for example,

		     [[	"?" = ${(~j.|.)array} ]]

	      treats `|' as a pattern and succeeds if and only if $array  con-
	      tains  the  string  `?' as an element.  The ~ may	be repeated to
	      toggle the behaviour; its	effect only lasts to the  end  of  the
	      parenthesised group.

	      Join  the	 words of arrays together using	string as a separator.
	      Note that	this occurs before field splitting  by	the  s:string:
	      flag or the SH_WORD_SPLIT	option.

	      Pad  the	resulting  words on the	left.  Each word will be trun-
	      cated if required	and placed in a	field expr characters wide.

	      The arguments :string1: and :string2: are	optional; neither, the
	      first, or	both may be given.  Note that the same pairs of	delim-
	      iters must be used for each of the three arguments.   The	 space
	      to  the  left will be filled with	string1	(concatenated as often
	      as needed) or spaces if string1 is not given.  If	 both  string1
	      and  string2 are given, string2 is inserted once directly	to the
	      left of each word, truncated if  necessary,  before  string1  is
	      used to produce any remaining padding.

	      If either	of string1 or string2 is present but empty, i.e. there
	      are two delimiters together at that point, the  first  character
	      of $IFS is used instead.

	      If  the  MULTIBYTE  option  is in	effect,	the flag m may also be
	      given, in	which case widths will be used for the calculation  of
	      padding;	otherwise  individual multibyte	characters are treated
	      as occupying one unit of width.

	      If the MULTIBYTE option is not  in  effect,  each	 byte  in  the
	      string is	treated	as occupying one unit of width.

	      Control  characters are always assumed to	be one unit wide; this
	      allows the mechanism to be used for  generating  repetitions  of
	      control characters.

       m      Only  useful together with one of	the flags l or r or with the #
	      length operator when the MULTIBYTE option	is in effect.  Use the
	      character	 width	reported by the	system in calculating how much
	      of the string it occupies	or the overall length of  the  string.
	      Most printable characters	have a width of	one unit, however cer-
	      tain Asian character sets	and certain special effects use	 wider
	      characters; combining characters have zero width.	 Non-printable
	      characters are arbitrarily counted as zero width;	how they would
	      actually be displayed will vary.

	      If  the  m  is repeated, the character either counts zero	(if it
	      has zero width), else one.  For printable	character strings this
	      has  the	effect of counting the number of glyphs	(visibly sepa-
	      rate characters),	except for the case where combining characters
	      themselves have non-zero width (true in certain alphabets).

	      As  l, but pad the words on the right and	insert string2 immedi-
	      ately to the right of the	string to be padded.

	      Left and right padding may be used together.  In this  case  the
	      strategy	is  to	apply  left padding to the first half width of
	      each of the resulting words, and right  padding  to  the	second
	      half.   If  the string to	be padded has odd width	the extra pad-
	      ding is applied on the left.

	      Force field splitting at the  separator  string.	 Note  that  a
	      string  of  two  or  more	characters means that all of them must
	      match in sequence; this differs from the	treatment  of  two  or
	      more  characters	in the IFS parameter.  See also	the = flag and
	      the SH_WORD_SPLIT	option.	 An empty string may also be given  in
	      which case every character will be a separate element.

	      For  historical  reasons,	 the  usual behaviour that empty array
	      elements are retained  inside  double  quotes  is	 disabled  for
	      arrays generated by splitting; hence the following:

		     print -l "${(s.:.)line}"

	      produces	two  lines  of output for one and three	and elides the
	      empty field.  To override	this behaviour,	supply the `(@)'  flag
	      as well, i.e.  "${(@s.:.)line}".

	      As z but takes a combination of option letters between a follow-
	      ing pair of delimiter characters.	 With no options the effect is
	      identical	to z.  (Z+c+) causes comments to be parsed as a	string
	      and retained; any	field in the resulting array beginning with an
	      unquoted comment character is a comment.	(Z+C+) causes comments
	      to be parsed and removed.	 The rule for  comments	 is  standard:
	      anything	between	 a  word  starting with	the third character of
	      $HISTCHARS, default #, up	to the	next  newline  is  a  comment.
	      (Z+n+) causes unquoted newlines to be treated as ordinary	white-
	      space, else they are treated as if they are  shell  code	delim-
	      iters  and converted to semicolons.  Options are combined	within
	      the same set of delimiters, e.g. (Z+Cn+).

	      The underscore (_) flag is reserved for future use.  As of  this
	      revision of zsh, there are no valid flags; anything following an
	      underscore, other	than an	empty pair of delimiters,  is  treated
	      as an error, and the flag	itself has no effect.

       The  following  flags  are meaningful with the ${...#...} or ${...%...}
       forms.  The S and I flags may also be used with the ${.../...} forms.

       S      Search substrings	as well	as beginnings or ends;	with  #	 start
	      from  the	beginning and with % start from	the end	of the string.
	      With  substitution  via  ${.../...}  or  ${...//...},  specifies
	      non-greedy matching, i.e.	that the shortest instead of the long-
	      est match	should be replaced.

	      Search the exprth	match (where  expr  evaluates  to  a  number).
	      This only	applies	when searching for substrings, either with the
	      S	flag, or with ${.../...} (only the  exprth  match  is  substi-
	      tuted)  or  ${...//...} (all matches from	the exprth on are sub-
	      stituted).  The default is to take the first match.

	      The exprth match is counted such that there  is  either  one  or
	      zero matches from	each starting position in the string, although
	      for global substitution matches  overlapping  previous  replace-
	      ments  are  ignored.  With the ${...%...}	and ${...%%...}	forms,
	      the starting position for	the match moves	backwards from the end
	      as the index increases, while with the other forms it moves for-
	      ward from	the start.

	      Hence with the string
		     which switch is the right switch for Ipswich?
	      substitutions of the form	${(SI:N:)string#w*ch} as  N  increases
	      from  1  will  match  and	 remove	 `which', `witch', `witch' and
	      `wich'; the form using `##' will match and remove	`which	switch
	      is the right switch for Ipswich',	`witch is the right switch for
	      Ipswich',	`witch for Ipswich' and	`wich'.	 The  form  using  `%'
	      will  remove  the	same matches as	for `#', but in	reverse	order,
	      and the form using `%%' will remove the same matches as for `##'
	      in reverse order.

       B      Include the index	of the beginning of the	match in the result.

       E      Include the index	one character past the end of the match	in the
	      result (note this	is inconsistent	with other uses	 of  parameter

       M      Include the matched portion in the result.

       N      Include the length of the	match in the result.

       R      Include the unmatched portion in the result (the Rest).

       Here  is	 a  summary  of	 the rules for substitution; this assumes that
       braces are present around the substitution, i.e.	${...}.	 Some particu-
       lar  examples  are  given  below.   Note	that the Zsh Development Group
       accepts no responsibility for any brain damage which may	 occur	during
       the reading of the following rules.

       1. Nested substitution
	      If  multiple  nested  ${...}  forms are present, substitution is
	      performed	from the inside	outwards.  At each level, the  substi-
	      tution takes account of whether the current value	is a scalar or
	      an array,	whether	the whole substitution is  in  double  quotes,
	      and  what	 flags	are supplied to	the current level of substitu-
	      tion, just as if the nested  substitution	 were  the  outermost.
	      The  flags are not propagated up to enclosing substitutions; the
	      nested substitution will return either a scalar or an  array  as
	      determined by the	flags, possibly	adjusted for quoting.  All the
	      following	steps take place where applicable  at  all  levels  of

	      Note  that,  unless the `(P)' flag is present, the flags and any
	      subscripts apply directly	to the value of	the  nested  substitu-
	      tion;  for  example, the expansion ${${foo}} behaves exactly the
	      same as ${foo}.  When the	`(P)' flag is present in a nested sub-
	      stitution, the other substitution	rules are applied to the value
	      before it	is interpreted as a name, so ${${(P)foo}}  may	differ
	      from ${(P)foo}.

	      At  each	nested	level  of  substitution, the substituted words
	      undergo all forms	of single-word substitution (i.e. not filename
	      generation),  including  command substitution, arithmetic	expan-
	      sion and filename	expansion (i.e.	leading	~ and =).   Thus,  for
	      example,	${${:-=cat}:h}	expands	to the directory where the cat
	      program resides.	(Explanation: the internal substitution	has no
	      parameter	 but  a	default	value =cat, which is expanded by file-
	      name expansion to	a  full	 path;	the  outer  substitution  then
	      applies  the  modifier  :h  and  takes the directory part	of the

       2. Internal parameter flags
	      Any parameter flags set by one of	the  typeset  family  of  com-
	      mands,  in particular the	-L, -R,	-Z, -u and -l options for pad-
	      ding and capitalization, are applied directly to	the  parameter
	      value.  Note these flags are options to the command, e.g.	`type-
	      set -Z'; they are	not the	same as	the flags used within  parame-
	      ter substitutions.

	      At the outermost level of	substitution, the `(P)'	flag (rule 4.)
	      ignores these transformations and	uses the unmodified  value  of
	      the  parameter  as the name to be	replaced.  This	is usually the
	      desired behavior because padding may make	 the  value  syntacti-
	      cally illegal as a parameter name, but if	capitalization changes
	      are desired, use the ${${(P)foo}}	form (rule 25.).

       3. Parameter subscripting
	      If the value is a	raw parameter reference	with a subscript, such
	      as  ${var[3]}, the effect	of subscripting	is applied directly to
	      the parameter.  Subscripts are evaluated left to	right;	subse-
	      quent  subscripts	 apply to the scalar or	array value yielded by
	      the previous subscript.  Thus if var is an  array,  ${var[1][2]}
	      is the second character of the first word, but ${var[2,4][2]} is
	      the entire third word (the second	word of	the range of words two
	      through  four  of	the original array).  Any number of subscripts
	      may appear.  Flags such as  `(k)'	 and  `(v)'  which  alter  the
	      result of	subscripting are applied.

       4. Parameter name replacement
	      At  the  outermost  level	 of  nesting  only,  the `(P)' flag is
	      applied.	This treats the	value  so  far	as  a  parameter  name
	      (which  may  include  a  subscript expression) and replaces that
	      with the corresponding value.  This replacement occurs later  if
	      the `(P)'	flag appears in	a nested substitution.

	      If  the  value  so far names a parameter that has	internal flags
	      (rule 2.), those internal	flags are applied  to  the  new	 value
	      after replacement.

       5. Double-quoted	joining
	      If  the  value after this	process	is an array, and the substitu-
	      tion appears in double quotes, and neither an `(@)' flag	nor  a
	      `#'  length operator is present at the current level, then words
	      of the value are joined with the first character of the  parame-
	      ter  $IFS,  by  default  a space,	between	each word (single word
	      arrays are not modified).	 If the	`(j)' flag is present, that is
	      used for joining instead of $IFS.

       6. Nested subscripting
	      Any  remaining  subscripts  (i.e.	 of a nested substitution) are
	      evaluated	at this	point, based on	whether	the value is an	 array
	      or  a scalar.  As	with 3., multiple subscripts can appear.  Note
	      that ${foo[2,4][2]} is thus equivalent to	${${foo[2,4]}[2]}  and
	      also  to "${${(@)foo[2,4]}[2]}" (the nested substitution returns
	      an array in both cases), but  not	 to  "${${foo[2,4]}[2]}"  (the
	      nested substitution returns a scalar because of the quotes).

       7. Modifiers
	      Any  modifiers, as specified by a	trailing `#', `%', `/' (possi-
	      bly doubled) or by a set of modifiers of the  form  `:...'  (see
	      the section `Modifiers' in the section `History Expansion'), are
	      applied to the words of the value	at this	level.

       8. Character evaluation
	      Any `(#)'	flag is	applied, evaluating the	result so far  numeri-
	      cally as a character.

       9. Length
	      Any  initial  `#'	modifier, i.e. in the form ${#var}, is used to
	      evaluate the length of the expression so far.

       10. Forced joining
	      If the `(j)' flag	is present, or no `(j)'	flag  is  present  but
	      the  string is to	be split as given by rule 11., and joining did
	      not take place at	rule 5., any words in  the  value  are	joined
	      together	using  the given string	or the first character of $IFS
	      if none.	Note that the `(F)' flag implicitly supplies a	string
	      for joining in this manner.

       11. Simple word splitting
	      If one of	the `(s)' or `(f)' flags are present, or the `=' spec-
	      ifier was	present	(e.g. ${=var}),	the word is  split  on	occur-
	      rences  of  the  specified string, or (for = with	neither	of the
	      two flags	present) any of	the characters in $IFS.

	      If no `(s)', `(f)' or `='	was given, but the word	is not	quoted
	      and the option SH_WORD_SPLIT is set, the word is split on	occur-
	      rences of	any of the characters in $IFS.	Note this  step,  too,
	      takes place at all levels	of a nested substitution.

       12. Case	modification
	      Any  case	 modification  from  one  of the flags `(L)', `(U)' or
	      `(C)' is applied.

       13. Escape sequence replacement
	      First any	replacements from the `(g)' flag are  performed,  then
	      any  prompt-style	 formatting  from the `(%)' family of flags is

       14. Quote application
	      Any quoting or unquoting using `(q)' and `(Q)' and related flags
	      is applied.

       15. Directory naming
	      Any directory name substitution using `(D)' flag is applied.

       16. Visibility enhancement
	      Any  modifications  to  make  characters visible using the `(V)'
	      flag are applied.

       17. Lexical word	splitting
	      If the '(z)' flag	or one of the  forms  of  the  '(Z)'  flag  is
	      present,	the  word is split as if it were a shell command line,
	      so that quotation	marks and other	 metacharacters	 are  used  to
	      decide  what constitutes a word.	Note this form of splitting is
	      entirely distinct	from that described by rule 11.: it  does  not
	      use $IFS,	and does not cause forced joining.

       18. Uniqueness
	      If the result is an array	and the	`(u)' flag was present,	dupli-
	      cate elements are	removed	from the array.

       19. Ordering
	      If the result is still an	array and one of the  `(o)'  or	 `(O)'
	      flags was	present, the array is reordered.

       20. RC_EXPAND_PARAM
	      At  this	point the decision is made whether any resulting array
	      elements are to be combined element by element with  surrounding
	      text,  as	 given by either the RC_EXPAND_PARAM option or the `^'

       21. Re-evaluation
	      Any `(e)'	flag is	 applied  to  the  value,  forcing  it	to  be
	      re-examined  for	new parameter substitutions, but also for com-
	      mand and arithmetic substitutions.

       22. Padding
	      Any padding of the value by the `(l.fill.)' or `(r.fill.)' flags
	      is applied.

       23. Semantic joining
	      In  contexts where expansion semantics requires a	single word to
	      result, all words	are rejoined with the first character  of  IFS
	      between.	 So  in	 `${(P)${(f)lines}}'  the value	of ${lines} is
	      split at newlines, but then must	be  joined  again  before  the
	      `(P)' flag can be	applied.

	      If a single word is not required,	this rule is skipped.

       24. Empty argument removal
	      If  the  substitution  does  not	appear	in  double quotes, any
	      resulting	zero-length argument, whether from a scalar or an ele-
	      ment  of an array, is elided from	the list of arguments inserted
	      into the command line.

	      Strictly speaking, the removal happens later as the same happens
	      with other forms of substitution;	the point to note here is sim-
	      ply that it occurs after any of the above	parameter  operations.

       25. Nested parameter name replacement
	      If  the  `(P)'  flag is present and rule 4. has not applied, the
	      value so far is treated as a parameter name (which may include a
	      subscript	expression) and	replaced with the corresponding	value,
	      with internal flags (rule	2.) applied to the new value.

       The flag	f is useful to split  a	 double-quoted	substitution  line  by
       line.   For  example, ${(f)"$(<file)"} substitutes the contents of file
       divided so that each line is an element of the resulting	 array.	  Com-
       pare  this with the effect of $(<file) alone, which divides the file up
       by words, or the	same inside double quotes, which makes the entire con-
       tent of the file	a single string.

       The  following  illustrates  the	rules for nested parameter expansions.
       Suppose that $foo contains the array (bar baz):

	      This produces the	 result	 b.   First,  the  inner  substitution
	      "${foo}",	 which	has  no	array (@) flag,	produces a single word
	      result "bar baz".	 The outer substitution	"${(@)...[1]}" detects
	      that this	is a scalar, so	that (despite the `(@)'	flag) the sub-
	      script picks the first character.

	      This produces the	result `bar'.  In this case, the inner substi-
	      tution  "${(@)foo}"  produces  the array `(bar baz)'.  The outer
	      substitution "${...[1]}" detects that this is an array and picks
	      the first	word.  This is similar to the simple case "${foo[1]}".

       As an example of	the rules for word splitting and joining, suppose $foo
       contains	the array `(ax1	bx1)'.	Then

	      produces the words `a', `1 b' and	`1'.

	      produces `a', `1', `b' and `1'.

	      produces	`a'  and ` b' (note the	extra space).  As substitution
	      occurs before either joining or splitting, the operation	 first
	      generates	 the  modified	array (ax bx), which is	joined to give
	      "ax bx", and then	split to give `a', ` b'	 and  `'.   The	 final
	      empty string will	then be	elided,	as it is not in	double quotes.

       A command enclosed in parentheses  preceded  by	a  dollar  sign,  like
       `$(...)',  or quoted with grave accents,	like ``...`', is replaced with
       its standard output, with any trailing newlines deleted.	 If  the  sub-
       stitution  is  not enclosed in double quotes, the output	is broken into
       words using the IFS parameter.  The substitution	`$(cat	foo)'  may  be
       replaced	 by  the  equivalent but faster	`$(<foo)'.  In either case, if
       the option GLOB_SUBST is	set, the output	is eligible for	filename  gen-

       A  string  of  the  form	`$[exp]' or `$((exp))' is substituted with the
       value of	the arithmetic expression exp.	exp is subjected to  parameter
       expansion,  command  substitution and arithmetic	expansion before it is
       evaluated.  See the section `Arithmetic Evaluation'.

       A string	of the form `foo{xx,yy,zz}bar' is expanded to  the  individual
       words  `fooxxbar',  `fooyybar'  and `foozzbar'.	Left-to-right order is
       preserved.  This	construct may be nested.   Commas  may	be  quoted  in
       order to	include	them literally in a word.

       An  expression of the form `{n1..n2}', where n1 and n2 are integers, is
       expanded	to every number	between	n1 and n2 inclusive.  If either	number
       begins with a zero, all the resulting numbers will be padded with lead-
       ing zeroes to that minimum width, but for negative numbers the -	 char-
       acter  is also included in the width.  If the numbers are in decreasing
       order the resulting sequence will also be in decreasing order.

       An expression of	the form `{n1..n2..n3}', where	n1,  n2,  and  n3  are
       integers,  is  expanded	as  above, but only every n3th number starting
       from n1 is output.  If n3 is negative the numbers are output in reverse
       order, this is slightly different from simply swapping n1 and n2	in the
       case that the step n3 doesn't evenly divide the	range.	 Zero  padding
       can  be	specified  in  any  of the three numbers, specifying it	in the
       third can be useful to pad for example `{-99..100..01}'	which  is  not
       possible	 to  specify by	putting	a 0 on either of the first two numbers
       (i.e. pad to two	characters).

       An expression of	the form `{c1..c2}', where c1 and c2 are single	 char-
       acters  (which may be multibyte characters), is expanded	to every char-
       acter in	the range from c1 to c2	in whatever character sequence is used
       internally.  For	characters with	code points below 128 this is US ASCII
       (this is	the only case most users will need).  If any intervening char-
       acter  is  not  printable,  appropriate	quotation is used to render it
       printable.  If the character sequence is	reversed,  the	output	is  in
       reverse order, e.g. `{d..a}' is substituted as `d c b a'.

       If  a  brace  expression	 matches  none	of the above forms, it is left
       unchanged, unless the option  BRACE_CCL	(an  abbreviation  for	`brace
       character  class')  is  set.  In	that case, it is expanded to a list of
       the individual characters between the braces sorted into	the  order  of
       the characters in the ASCII character set (multibyte characters are not
       currently handled).  The	syntax is similar to  a	 [...]	expression  in
       filename	 generation:  `-'  is  treated	specially to denote a range of
       characters, but `^' or `!' as the first character is treated  normally.
       For  example, `{abcdef0-9}' expands to 16 words 0 1 2 3 4 5 6 7 8 9 a b
       c d e f.

       Note that brace expansion is not	part  of  filename  generation	(glob-
       bing);  an  expression  such  as	*/{foo,bar} is split into two separate
       words */foo and */bar before filename generation	takes place.  In  par-
       ticular,	 note  that  this  is  liable to produce a `no match' error if
       either of the two expressions does not match; this is to	be  contrasted
       with  */(foo|bar),  which  is treated as	a single pattern but otherwise
       has similar effects.

       To combine brace	expansion with array expansion,	see the	${^spec}  form
       described in the	section	Parameter Expansion above.

       Each  word  is checked to see if	it begins with an unquoted `~'.	 If it
       does, then the word up to a `/',	or the end of the word if there	is  no
       `/',  is	 checked  to  see  if it can be	substituted in one of the ways
       described here.	If so, then  the  `~'  and  the	 checked  portion  are
       replaced	with the appropriate substitute	value.

       A `~' by	itself is replaced by the value	of $HOME.  A `~' followed by a
       `+' or a	`-' is replaced	by  current  or	 previous  working  directory,

       A  `~'  followed	by a number is replaced	by the directory at that posi-
       tion in the directory stack.  `~0' is equivalent	to `~+', and  `~1'  is
       the  top	 of  the  stack.  `~+' followed	by a number is replaced	by the
       directory at that position in the directory stack.  `~+0' is equivalent
       to  `~+', and `~+1' is the top of the stack.  `~-' followed by a	number
       is replaced by the directory that many positions	from the bottom	of the
       stack.	`~-0'  is  the	bottom	of  the	stack.	The PUSHD_MINUS	option
       exchanges the effects of	`~+' and `~-' where they  are  followed	 by  a

   Dynamic named directories
       If  the	function  zsh_directory_name  exists,  or  the	shell variable
       zsh_directory_name_functions exists and contains	an array  of  function
       names,  then the	functions are used to implement	dynamic	directory nam-
       ing.  The functions are tried in	order until one	returns	 status	 zero,
       so it is	important that functions test whether they can handle the case
       in question and return an appropriate status.

       A `~' followed by a  string  namstr  in	unquoted  square  brackets  is
       treated	specially  as  a  dynamic directory name.  Note	that the first
       unquoted	closing	square bracket always terminates  namstr.   The	 shell
       function	 is  passed two	arguments: the string n	(for name) and namstr.
       It should either	set the	array reply to a single	element	which  is  the
       directory  corresponding	 to the	name and return	status zero (executing
       an assignment as	the last  statement  is	 usually  sufficient),	or  it
       should return status non-zero.  In the former case the element of reply
       is used as the directory; in the	latter case the	substitution is	deemed
       to  have	 failed.  If all functions fail	and the	option NOMATCH is set,
       an error	results.

       The functions defined as	above are also used to see if a	directory  can
       be turned into a	name, for example when printing	the directory stack or
       when expanding %~ in prompts.  In this case each	function is passed two
       arguments:  the	string d (for directory) and the candidate for dynamic
       naming.	The function should either  return  non-zero  status,  if  the
       directory  cannot  be named by the function, or it should set the array
       reply to	consist	of two elements: the first is the dynamic name for the
       directory (as would appear within `~[...]'), and	the second is the pre-
       fix length of the directory to be replaced.  For	example, if the	 trial
       directory   is	/home/myname/src/zsh   and   the   dynamic   name  for
       /home/myname/src	(which has 16 characters) is s,	then the function sets

	      reply=(s 16)

       The  directory  name so returned	is compared with possible static names
       for parts of the	directory path,	as described below; it is used if  the
       prefix  length  matched (16 in the example) is longer than that matched
       by any static name.

       It is not a requirement that a function implements both n and d	calls;
       for  example,  it  might	 be  appropriate  for certain dynamic forms of
       expansion not to	be contracted to names.	 In that case  any  call  with
       the first argument d should cause a non-zero status to be returned.

       The  completion system calls `zsh_directory_name	c' followed by equiva-
       lent calls to elements of the array zsh_directory_name_functions, if it
       exists,	in  order to complete dynamic names for	directories.  The code
       for this	should be as for any other completion function as described in

       As a working example, here is a function	that expands any dynamic names
       beginning with the string p: to directories  below  /home/pws/perforce.
       In  this	 simple	 case a	static name for	the directory would be just as

	      zsh_directory_name() {
		emulate	-L zsh
		setopt extendedglob
		local -a match mbegin mend
		if [[ $1 = d ]]; then
		  # turn the directory into a name
		  if [[	$2 = (#b)(/home/pws/perforce/)([^/]##)*	]]; then
		    typeset -ga	reply
		    reply=(p:$match[2] $(( ${#match[1]}	+ ${#match[2]} )) )
		    return 1
		elif [[	$1 = n ]]; then
		  # turn the name into a directory
		  [[ $2	!= (#b)p:(?*) ]] && return 1
		  typeset -ga reply
		elif [[	$1 = c ]]; then
		  # complete names
		  local	expl
		  local	-a dirs
		  _wanted dynamic-dirs expl 'dynamic directory'	compadd	-S\] -a	dirs
		  return 1
		return 0

   Static named	directories
       A `~' followed by anything not already covered consisting of any	number
       of  alphanumeric	 characters  or	underscore (`_'), hyphen (`-'),	or dot
       (`.') is	looked up as a named directory,	and replaced by	the  value  of
       that  named  directory  if found.  Named	directories are	typically home
       directories for users on	the system.  They may also be defined  if  the
       text  after the `~' is the name of a string shell parameter whose value
       begins with a `/'.  Note	that trailing slashes will be removed from the
       path  to	the directory (though the original parameter is	not modified).

       It is also possible to define directory names using the	-d  option  to
       the hash	builtin.

       When the	shell prints a path (e.g. when expanding %~ in prompts or when
       printing	the directory stack), the path is checked to see if it	has  a
       named  directory	 as  its  prefix.   If	so, then the prefix portion is
       replaced	with a `~' followed by the name	of the directory.  The shorter
       of  the two ways	of referring to	the directory is used, i.e. either the
       directory name or the full path;	the name is used if they are the  same
       length.	 The parameters	$PWD and $OLDPWD are never abbreviated in this

   `=' expansion
       If a word begins	with an	unquoted `=' and the EQUALS option is set, the
       remainder  of the word is taken as the name of a	command.  If a command
       exists by that name, the	word is	replaced by the	full pathname  of  the

       Filename	 expansion  is performed on the	right hand side	of a parameter
       assignment, including those appearing after  commands  of  the  typeset
       family.	 In  this  case,  the  right  hand  side  will be treated as a
       colon-separated list in the manner of the PATH parameter, so that a `~'
       or  an  `=' following a `:' is eligible for expansion.  All such	behav-
       iour can	be disabled by quoting the `~',	the `=', or the	whole  expres-
       sion (but not simply the	colon);	the EQUALS option is also respected.

       If  the option MAGIC_EQUAL_SUBST	is set,	any unquoted shell argument in
       the form	`identifier=expression'	becomes	eligible for file expansion as
       described  in  the  previous  paragraph.	  Quoting  the	first `=' also
       inhibits	this.

       If a word contains an unquoted instance of one of the  characters  `*',
       `(',  `|',  `<',	 `[', or `?', it is regarded as	a pattern for filename
       generation, unless the GLOB option  is  unset.	If  the	 EXTENDED_GLOB
       option is set, the `^' and `#' characters also denote a pattern;	other-
       wise they are not treated specially by the shell.

       The word	is replaced with a list	of sorted  filenames  that  match  the
       pattern.	  If  no  matching  pattern is found, the shell	gives an error
       message,	unless the NULL_GLOB option is set, in which case the word  is
       deleted;	 or unless the NOMATCH option is unset,	in which case the word
       is left unchanged.

       In filename generation, the character `/' must be  matched  explicitly;
       also, a `.' must	be matched explicitly at the beginning of a pattern or
       after a `/', unless the GLOB_DOTS option	is set.	 No  filename  genera-
       tion pattern matches the	files `.' or `..'.  In other instances of pat-
       tern matching, the `/' and `.' are not treated specially.

   Glob	Operators
       *      Matches any string, including the	null string.

       ?      Matches any character.

       [...]  Matches any of the enclosed characters.	Ranges	of  characters
	      can  be  specified by separating two characters by a `-'.	 A `-'
	      or `]' may be matched by including it as the first character  in
	      the  list.   There are also several named	classes	of characters,
	      in the form `[:name:]' with the following	meanings.   The	 first
	      set  use the macros provided by the operating system to test for
	      the given	character combinations,	 including  any	 modifications
	      due to local language settings, see ctype(3):

		     The character is alphanumeric

		     The character is alphabetic

		     The  character  is	7-bit, i.e. is a single-byte character
		     without the top bit set.

		     The character is either space or tab

		     The character is a	control	character

		     The character is a	decimal	digit

		     The character is a	printable character other than	white-

		     The character is a	lowercase letter

		     The character is printable

		     The  character  is	printable but neither alphanumeric nor

		     The character is whitespace

		     The character is an uppercase letter

		     The character is a	hexadecimal digit

	      Another set of named classes is handled internally by the	 shell
	      and is not sensitive to the locale:

		     The  character is allowed to form part of a shell identi-
		     fier, such	as a parameter name

		     The character is used as an input field  separator,  i.e.
		     is	contained in the IFS parameter

		     The  character  is	 an IFS	white space character; see the
		     documentation for IFS in the zshparam(1) manual page.

		     Matches a byte that starts	an incomplete multibyte	 char-
		     acter.   Note  that  there	may be a sequence of more than
		     one bytes that taken together form	the prefix of a	multi-
		     byte  character.	To  test  for a	potentially incomplete
		     byte sequence, use	the pattern `[[:INCOMPLETE:]]*'.  This
		     will  never match a sequence starting with	a valid	multi-
		     byte character.

		     Matches a byte that does  not  start  a  valid  multibyte
		     character.	  Note	this  may be a continuation byte of an
		     incomplete	multibyte character as any part	of a multibyte
		     string  consisting	 of  invalid  and incomplete multibyte
		     characters	is treated as single bytes.

		     The character is treated as part of a word; this test  is
		     sensitive to the value of the WORDCHARS parameter

	      Note  that the square brackets are additional to those enclosing
	      the whole	set of characters, so to test for  a  single  alphanu-
	      meric  character	you  need `[[:alnum:]]'.  Named	character sets
	      can be used alongside other types, e.g. `[[:alpha:]0-9]'.

       [!...] Like [...], except that it matches any character which is	not in
	      the given	set.

	      Matches  any  number  in the range x to y, inclusive.  Either of
	      the numbers may be omitted to make the range  open-ended;	 hence
	      `<->' matches any	number.	 To match individual digits, the [...]
	      form is more efficient.

	      Be careful when using other wildcards adjacent  to  patterns  of
	      this  form;  for	example, <0-9>*	will actually match any	number
	      whatsoever at the	start of the string, since  the	 `<0-9>'  will
	      match  the first digit, and the `*' will match any others.  This
	      is a trap	for the	unwary,	but is in fact	an  inevitable	conse-
	      quence  of  the rule that	the longest possible match always suc-
	      ceeds.  Expressions such as  `<0-9>[^[:digit:]]*'	 can  be  used

       (...)  Matches  the  enclosed  pattern.	This is	used for grouping.  If
	      the KSH_GLOB option is set, then a `@', `*',  `+',  `?'  or  `!'
	      immediately  preceding the `(' is	treated	specially, as detailed
	      below. The option	SH_GLOB	prevents bare parentheses  from	 being
	      used in this way,	though the KSH_GLOB option is still available.

	      Note that	grouping cannot	extend over multiple  directories:  it
	      is  an error to have a `/' within	a group	(this only applies for
	      patterns used in filename	generation).  There is one  exception:
	      a	group of the form (pat/)# appearing as a complete path segment
	      can match	a sequence of directories.  For	example, foo/(a*/)#bar
	      matches foo/bar, foo/any/bar, foo/any/anyother/bar, and so on.

       x|y    Matches  either x	or y.  This operator has lower precedence than
	      any other.  The `|' character must  be  within  parentheses,  to
	      avoid interpretation as a	pipeline.

       ^x     (Requires	EXTENDED_GLOB to be set.)  Matches anything except the
	      pattern x.  This has a higher precedence than `/', so `^foo/bar'
	      will  search  directories	in `.' except `./foo' for a file named

       x~y    (Requires	EXTENDED_GLOB to be set.)  Match anything that matches
	      the  pattern  x but does not match y.  This has lower precedence
	      than any operator	except `|', so `*/*~foo/bar' will  search  for
	      all  files in all	directories in `.'  and	then exclude `foo/bar'
	      if there was such	a match.  Multiple patterns can	be excluded by
	      `foo~bar~baz'.   In  the	exclusion pattern (y), `/' and `.' are
	      not treated specially the	way they usually are in	globbing.

       x#     (Requires	EXTENDED_GLOB to be set.)  Matches zero	or more	occur-
	      rences  of  the  pattern	x.  This operator has high precedence;
	      `12#' is equivalent to `1(2#)', rather than `(12)#'.  It	is  an
	      error  for  an  unquoted `#' to follow something which cannot be
	      repeated;	this includes an empty string, a pattern already  fol-
	      lowed  by	 `##',	or parentheses when part of a KSH_GLOB pattern
	      (for example, `!(foo)#' is  invalid  and	must  be  replaced  by

       x##    (Requires	 EXTENDED_GLOB to be set.)  Matches one	or more	occur-
	      rences of	the pattern x.	This  operator	has  high  precedence;
	      `12##' is	equivalent to `1(2##)',	rather than `(12)##'.  No more
	      than two active `#' characters may appear	together.   (Note  the
	      potential	 clash with glob qualifiers in the form	`1(2##)' which
	      should therefore be avoided.)

   ksh-like Glob Operators
       If the KSH_GLOB option is set, the effects of parentheses can be	 modi-
       fied by a preceding `@',	`*', `+', `?' or `!'.  This character need not
       be unquoted to have special effects, but	the `('	must be.

       @(...) Match the	pattern	in the parentheses.  (Like `(...)'.)

       *(...) Match any	number of occurrences.	(Like  `(...)#',  except  that
	      recursive	directory searching is not supported.)

       +(...) Match  at	 least	one  occurrence.  (Like	`(...)##', except that
	      recursive	directory searching is not supported.)

       ?(...) Match zero or one	occurrence.  (Like `(|...)'.)

       !(...) Match  anything  but  the	 expression  in	 parentheses.	 (Like

       The precedence of the operators given above is (highest)	`^', `/', `~',
       `|' (lowest); the remaining operators are simply	treated	from  left  to
       right  as  part of a string, with `#' and `##' applying to the shortest
       possible	preceding unit (i.e. a character, `?', `[...]',	`<...>', or  a
       parenthesised  expression).  As mentioned above,	a `/' used as a	direc-
       tory separator may not appear inside parentheses, while a `|'  must  do
       so;  in	patterns  used in other	contexts than filename generation (for
       example,	in case	statements and tests within `[[...]]'),	a `/'  is  not
       special;	 and  `/'  is  also  not special after a `~' appearing outside
       parentheses in a	filename pattern.

   Globbing Flags
       There are various flags which affect any	text to	their right up to  the
       end  of	the enclosing group or to the end of the pattern; they require
       the EXTENDED_GLOB option. All take the form (#X)	where X	may  have  one
       of the following	forms:

       i      Case insensitive:	 upper or lower	case characters	in the pattern
	      match upper or lower case	characters.

       l      Lower case characters in the pattern match upper or  lower  case
	      characters;  upper  case	characters  in	the pattern still only
	      match upper case characters.

       I      Case sensitive:  locally negates the effect of i or l from  that
	      point on.

       b      Activate backreferences for parenthesised	groups in the pattern;
	      this does	not work in filename generation.  When a pattern  with
	      a	 set  of active	parentheses is matched,	the strings matched by
	      the groups are stored in the array $match, the  indices  of  the
	      beginning	 of  the matched parentheses in	the array $mbegin, and
	      the indices of the end in	the array $mend, with the  first  ele-
	      ment  of	each  array  corresponding  to the first parenthesised
	      group, and so on.	 These arrays are not otherwise	special	to the
	      shell.   The  indices  use the same convention as	does parameter
	      substitution, so that elements of	$mend and $mbegin may be  used
	      in  subscripts;  the  KSH_ARRAYS	option	is respected.  Sets of
	      globbing flags are not considered	parenthesised groups; only the
	      first nine active	parentheses can	be referenced.

	      For example,

		     foo="a string with	a message"
		     if	[[ $foo	= (a|an)' '(#b)(*)' '* ]]; then
		       print ${foo[$mbegin[1],$mend[1]]}

	      prints  `string  with  a'.   Note	 that the first	parenthesis is
	      before the (#b) and does not create a backreference.

	      Backreferences work with all forms  of  pattern  matching	 other
	      than  filename generation, but note that when performing matches
	      on an entire array, such as ${array#pattern}, or a  global  sub-
	      stitution,  such	as  ${param//pat/repl},	 only the data for the
	      last match remains available.  In	the case  of  global  replace-
	      ments  this may still be useful.	See the	example	for the	m flag

	      The numbering of backreferences strictly follows	the  order  of
	      the  opening  parentheses	 from  left  to	 right	in the pattern
	      string, although sets of parentheses may be nested.   There  are
	      special rules for	parentheses followed by	`#' or `##'.  Only the
	      last match of the	parenthesis is remembered: for example,	in `[[
	      abab  =  (#b)([ab])#  ]]',  only	the  final  `b'	 is  stored in
	      match[1].	 Thus extra parentheses	may be necessary to match  the
	      complete	segment:  for  example,	 use `X((ab|cd)#)Y' to match a
	      whole string of either `ab' or `cd' between `X' and  `Y',	 using
	      the value	of $match[1] rather than $match[2].

	      If the match fails none of the parameters	is altered, so in some
	      cases it may be necessary	to  initialise	them  beforehand.   If
	      some  of	the  backreferences  fail to match -- which happens if
	      they are in an alternate branch which fails to match, or if they
	      are  followed  by	 #  and	matched	zero times -- then the matched
	      string is	set to the empty string, and the start and end indices
	      are set to -1.

	      Pattern  matching	 with  backreferences  is slightly slower than

       B      Deactivate backreferences, negating the effect  of  the  b  flag
	      from that	point on.

       cN,M   The flag (#cN,M) can be used anywhere that the # or ## operators
	      can be used except in the	expressions `(*/)#'  and  `(*/)##'  in
	      filename generation, where `/' has special meaning; it cannot be
	      combined with other globbing  flags  and	a  bad	pattern	 error
	      occurs  if  it is	misplaced.  It is equivalent to	the form {N,M}
	      in regular expressions.  The  previous  character	 or  group  is
	      required	to  match  between N and M times, inclusive.  The form
	      (#cN) requires exactly N matches;	(#c,M) is equivalent to	speci-
	      fying N as 0; (#cN,) specifies that there	is no maximum limit on
	      the number of matches.

       m      Set references to	the match data for the entire string  matched;
	      this is similar to backreferencing and does not work in filename
	      generation.  The flag must be in effect at the end of  the  pat-
	      tern, i.e. not local to a	group. The parameters $MATCH,  $MBEGIN
	      and $MEND	will be	set to the string matched and to  the  indices
	      of  the  beginning and end of the	string,	respectively.  This is
	      most useful in parameter substitutions, as otherwise the	string
	      matched is obvious.

	      For example,

		     arr=(veldt	jynx grimps waqf zho buck)
		     print ${arr//(#m)[aeiou]/${(U)MATCH}}

	      forces  all the matches (i.e. all	vowels)	into uppercase,	print-
	      ing `vEldt jynx grImps wAqf zhO bUck'.

	      Unlike backreferences, there is no speed penalty for using match
	      references,  other than the extra	substitutions required for the
	      replacement strings in cases such	as the example shown.

       M      Deactivate the m flag, hence no references to match data will be

       anum   Approximate  matching:  num  errors  are	allowed	 in the	string
	      matched by the pattern.  The rules for this are described	in the
	      next subsection.

       s, e   Unlike the other flags, these have only a	local effect, and each
	      must appear on its own:  `(#s)' and `(#e)' are  the  only	 valid
	      forms.   The  `(#s)' flag	succeeds only at the start of the test
	      string, and the `(#e)' flag succeeds only	at the end of the test
	      string;  they  correspond	 to  `^'  and  `$' in standard regular
	      expressions.  They are useful for	matching path segments in pat-
	      terns  other  than those in filename generation (where path seg-
	      ments  are  in  any  case	 treated  separately).	 For  example,
	      `*((#s)|/)test((#e)|/)*' matches a path segment `test' in	any of
	      the  following  strings:	 test,	 test/at/start,	  at/end/test,

	      Another	use   is   in	parameter  substitution;  for  example
	      `${array/(#s)A*Z(#e)}' will remove only  elements	 of  an	 array
	      which match the complete pattern `A*Z'.  There are other ways of
	      performing many operations of this type, however the combination
	      of  the substitution operations `/' and `//' with	the `(#s)' and
	      `(#e)' flags provides a single simple and	memorable method.

	      Note that	assertions of the form `(^(#s))' also work, i.e. match
	      anywhere	except at the start of the string, although this actu-
	      ally means `anything except a zero-length	portion	at  the	 start
	      of  the  string';	 you  need  to	use  `(""~(#s))'  to  match  a
	      zero-length portion of the string	not at the start.

       q      A	`q' and	everything up to the closing parenthesis of the	 glob-
	      bing  flags  are	ignored	by the pattern matching	code.  This is
	      intended to support the use of glob qualifiers, see below.   The
	      result is	that the pattern `(#b)(*).c(#q.)' can be used both for
	      globbing and for matching	against	a string.  In the former case,
	      the  `(#q.)'  will be treated as a glob qualifier	and the	`(#b)'
	      will not be useful, while	in the latter case the `(#b)' is  use-
	      ful  for	backreferences	and the	`(#q.)'	will be	ignored.  Note
	      that colon modifiers in the glob qualifiers are also not applied
	      in ordinary pattern matching.

       u      Respect the current locale in determining	the presence of	multi-
	      byte characters in a pattern, provided the  shell	 was  compiled
	      with  MULTIBYTE_SUPPORT.	 This  overrides the MULTIBYTE option;
	      the default behaviour is taken  from  the	 option.   Compare  U.
	      (Mnemonic:  typically  multibyte	characters are from Unicode in
	      the UTF-8	encoding, although any extension of ASCII supported by
	      the system library may be	used.)

       U      All  characters  are  considered	to be a	single byte long.  The
	      opposite of u.  This overrides the MULTIBYTE option.

       For example, the	test string  fooxx  can	 be  matched  by  the  pattern
       (#i)FOOXX,  but	not  by	 (#l)FOOXX, (#i)FOO(#I)XX or ((#i)FOOX)X.  The
       string (#ia2)readme specifies case-insensitive matching of readme  with
       up to two errors.

       When  using the ksh syntax for grouping both KSH_GLOB and EXTENDED_GLOB
       must be set and the left	parenthesis should be  preceded	 by  @.	  Note
       also that the flags do not affect letters inside	[...] groups, in other
       words (#i)[a-z] still matches only lowercase  letters.	Finally,  note
       that when examining whole paths case-insensitively every	directory must
       be searched for all files which match, so that a	pattern	 of  the  form
       (#i)/foo/bar/...	is potentially slow.

   Approximate Matching
       When  matching  approximately,  the  shell  keeps a count of the	errors
       found, which cannot exceed the number specified in the  (#anum)	flags.
       Four types of error are recognised:

       1.     Different	characters, as in fooxbar and fooybar.

       2.     Transposition of characters, as in banana	and abnana.

       3.     A	 character  missing  in	the target string, as with the pattern
	      road and target string rod.

       4.     An extra character appearing in the target string, as with stove
	      and strove.

       Thus,  the pattern (#a3)abcd matches dcba, with the errors occurring by
       using the first rule twice and the second once, grouping	the string  as
       [d][cb][a] and [a][bc][d].

       Non-literal  parts of the pattern must match exactly, including charac-
       ters in character ranges: hence (#a1)???	  matches  strings  of	length
       four,  by  applying  rule  4  to	 an empty part of the pattern, but not
       strings of length two, since all	the ? must  match.   Other  characters
       which  must  match  exactly  are	 initial dots in filenames (unless the
       GLOB_DOTS option	is set), and all slashes in filenames, so that a/bc is
       two errors from ab/c (the slash cannot be transposed with another char-
       acter).	Similarly, errors are counted  separately  for	non-contiguous
       strings in the pattern, so that (ab|cd)ef is two	errors from aebf.

       When  using  exclusion  via  the	 ~  operator,  approximate matching is
       treated entirely	separately for the excluded part and must be activated
       separately.  Thus, (#a1)README~READ_ME matches READ.ME but not READ_ME,
       as the trailing READ_ME is  matched  without  approximation.   However,
       (#a1)README~(#a1)READ_ME	does not match any pattern of the form READ?ME
       as all such forms are now excluded.

       Apart from exclusions, there is only one	overall	error count;  however,
       the  maximum  errors  allowed  may  be altered locally, and this	can be
       delimited by grouping.  For example, (#a1)cat((#a0)dog)fox  allows  one
       error in	total, which may not occur in the dog section, and the pattern
       (#a1)cat(#a0)dog(#a1)fox	is equivalent.	Note that the point  at	 which
       an  error is first found	is the crucial one for establishing whether to
       use  approximation;  for	 example,  (#a1)abc(#a0)xyz  will  not	 match
       abcdxyz,	 because  the  error occurs at the `x',	where approximation is
       turned off.

       Entire  path  segments  may   be	  matched   approximately,   so	  that
       `(#a1)/foo/d/is/available/at/the/bar' allows one	error in any path seg-
       ment.  This is much less	efficient than	without	 the  (#a1),  however,
       since  every  directory	in  the	 path  must  be	scanned	for a possible
       approximate match.  It is best to place the (#a1) after any  path  seg-
       ments which are known to	be correct.

   Recursive Globbing
       A pathname component of the form	`(foo/)#' matches a path consisting of
       zero or more directories	matching the pattern foo.

       As a shorthand, `**/' is	equivalent to `(*/)#'; note that  this	there-
       fore  matches files in the current directory as well as subdirectories.

	      ls (*/)#bar


	      ls **/bar

       does a recursive	directory search for files  named  `bar'  (potentially
       including the file `bar'	in the current directory).  This form does not
       follow symbolic links; the alternative form `***/' does,	but is	other-
       wise  identical.	  Neither of these can be combined with	other forms of
       globbing	within the same	path segment; in that case, the	`*'  operators
       revert to their usual effect.

       Even  shorter  forms  are  available when the option GLOB_STAR_SHORT is
       set.  In	that case if no	/ immediately follows a	**  or	***  they  are
       treated as if both a / plus a further * are present.  Hence:

	      setopt GLOBSTARSHORT
	      ls **.c

       is equivalent to

	      ls **/*.c

   Glob	Qualifiers
       Patterns	 used  for filename generation may end in a list of qualifiers
       enclosed	in parentheses.	 The qualifiers	specify	which  filenames  that
       otherwise  match	 the  given  pattern  will be inserted in the argument

       If the option BARE_GLOB_QUAL is set, then a trailing set	of parentheses
       containing  no `|' or `(' characters (or	`~' if it is special) is taken
       as a set	of glob	qualifiers.  A glob subexpression that would  normally
       be  taken  as  glob qualifiers, for example `(^x)', can be forced to be
       treated as part of the glob pattern by  doubling	 the  parentheses,  in
       this case producing `((^x))'.

       If  the option EXTENDED_GLOB is set, a different	syntax for glob	quali-
       fiers is	available, namely `(#qx)' where	x is  any  of  the  same  glob
       qualifiers  used	in the other format.  The qualifiers must still	appear
       at the end of the pattern.  However, with  this	syntax	multiple  glob
       qualifiers  may be chained together.  They are treated as a logical AND
       of the individual sets of flags.	 Also, as the syntax  is  unambiguous,
       the  expression	will  be  treated  as glob qualifiers just as long any
       parentheses contained within it are balanced; appearance	of `|',	`(' or
       `~'  does  not  negate the effect.  Note	that qualifiers	will be	recog-
       nised in	this form even if a bare glob qualifier	exists at the  end  of
       the  pattern, for example `*(#q*)(.)' will recognise executable regular
       files if	both options are set; however, mixed syntax should probably be
       avoided for the sake of clarity.	 Note that within conditions using the
       `[[' form the presence of a parenthesised expression (#q...) at the end
       of a string indicates that globbing should be performed;	the expression
       may include glob	qualifiers, but	it is also valid if it is simply (#q).
       This  does  not apply to	the right hand side of pattern match operators
       as the syntax already has special significance.

       A qualifier may be any one of the following:

       /      directories

       F      `full' (i.e. non-empty) directories.   Note  that	 the  opposite
	      sense (^F) expands to empty directories and all non-directories.
	      Use (/^F)	for empty directories.

       .      plain files

       @      symbolic links

       =      sockets

       p      named pipes (FIFOs)

       *      executable plain files (0100 or 0010 or 0001)

       %      device files (character or block special)

       %b     block special files

       %c     character	special	files

       r      owner-readable files (0400)

       w      owner-writable files (0200)

       x      owner-executable files (0100)

       A      group-readable files (0040)

       I      group-writable files (0020)

       E      group-executable files (0010)

       R      world-readable files (0004)

       W      world-writable files (0002)

       X      world-executable files (0001)

       s      setuid files (04000)

       S      setgid files (02000)

       t      files with the sticky bit	(01000)

       fspec  files with access	rights matching	spec. This spec	may be a octal
	      number optionally	preceded by a `=', a `+', or a `-'. If none of
	      these characters is given, the behavior is the same as for  `='.
	      The octal	number describes the mode bits to be expected, if com-
	      bined with a `=',	the value  given  must	match  the  file-modes
	      exactly,	with a `+', at least the bits in the given number must
	      be set in	the file-modes,	and with a `-',	the bits in the	number
	      must  not	be set.	Giving a `?' instead of	a octal	digit anywhere
	      in the  number  ensures  that  the  corresponding	 bits  in  the
	      file-modes  are  not checked, this is only useful	in combination
	      with `='.

	      If the qualifier `f' is followed by any other character anything
	      up  to the next matching character (`[', `{', and	`<' match `]',
	      `}', and `>' respectively, any other character  matches  itself)
	      is  taken	 as a list of comma-separated sub-specs. Each sub-spec
	      may be either an octal number as described above or  a  list  of
	      any of the characters `u', `g', `o', and `a', followed by	a `=',
	      a	`+', or	a `-', followed	by a list of  any  of  the  characters
	      `r',  `w',  `x', `s', and	`t', or	an octal digit.	The first list
	      of characters specify which access rights	are to be checked.  If
	      a	 `u'  is given,	those for the owner of the file	are used, if a
	      `g' is given, those of the group are checked,  a	`o'  means  to
	      test  those  of  other users, and	the `a'	says to	test all three
	      groups. The `=', `+', and	`-' again says how the modes are to be
	      checked  and  have  the  same meaning as described for the first
	      form above. The second list of  characters  finally  says	 which
	      access  rights  are to be	expected: `r' for read access, `w' for
	      write access, `x'	for the	right  to  execute  the	 file  (or  to
	      search a directory), `s' for the setuid and setgid bits, and `t'
	      for the sticky bit.

	      Thus, `*(f70?)' gives the	files for which	the  owner  has	 read,
	      write, and execute permission, and for which other group members
	      have no rights, independent of the permissions for other	users.
	      The  pattern `*(f-100)' gives all	files for which	the owner does
	      not have execute permission,  and	 `*(f:gu+w,o-rx:)'  gives  the
	      files  for  which	 the  owner and	the other members of the group
	      have at least write permission, and for which other users	 don't
	      have read	or execute permission.

       +cmd   The string will be executed as shell code.  The filename will be
	      included in the list if and only if the code returns a zero sta-
	      tus (usually the status of the last command).

	      In  the  first  form,  the first character after the `e' will be
	      used as a	separator and anything up to the next matching separa-
	      tor  will	 be taken  as the string; `[', `{', and	`<' match `]',
	      `}', and `>', respectively, while	any  other  character  matches
	      itself.  Note  that  expansions  must be quoted in the string to
	      prevent them  from  being	 expanded  before  globbing  is	 done.
	      string  is  then executed	as shell code.	The string globqual is
	      appended to the array zsh_eval_context the  duration  of	execu-

	      During  the  execution  of  string  the filename currently being
	      tested is	available in the parameter REPLY; the parameter	may be
	      altered  to a string to be inserted into the list	instead	of the
	      original filename.  In addition, the parameter reply may be  set
	      to an array or a string, which overrides the value of REPLY.  If
	      set to an	array, the latter is inserted into  the	 command  line
	      word by word.

	      For   example,  suppose  a  directory  contains  a  single  file
	      `lonely'.	 Then the  expression  `*(e:'reply=(${REPLY}{1,2})':)'
	      will cause the words `lonely1' and `lonely2' to be inserted into
	      the command line.	 Note the quoting of string.

	      The form +cmd has	the same  effect,  but	no  delimiters	appear
	      around  cmd.   Instead,  cmd is taken as the longest sequence of
	      characters following the + that are alphanumeric or  underscore.
	      Typically	cmd will be the	name of	a shell	function that contains
	      the appropriate test.  For example,

		     nt() { [[ $REPLY -nt $NTREF ]] }
		     ls	-l *(+nt)

	      lists all	files in the directory that have  been	modified  more
	      recently than reffile.

       ddev   files on the device dev

	      files having a link count	less than ct (-), greater than ct (+),
	      or equal to ct

       U      files owned by the effective user	ID

       G      files owned by the effective group ID

       uid    files owned by user ID id	if that	is a  number.	Otherwise,  id
	      specifies	a user name: the character after the `u' will be taken
	      as a separator and the string between it and the	next  matching
	      separator	will be	taken as a user	name.  The starting separators
	      `[', `{',	and `<'	match the final	separators `]',	`}', and  `>',
	      respectively;  any other character matches itself.  The selected
	      files are	those owned by this user.  For	example,  `u:foo:'  or
	      `u[foo]' selects files owned by user `foo'.

       gid    like uid but with	group IDs or names

	      files  accessed  exactly	n days ago.  Files accessed within the
	      last n days are selected using a	negative  value	 for  n	 (-n).
	      Files accessed more than n days ago are selected by a positive n
	      value (+n).  Optional unit specifiers `M', `w', `h', `m' or  `s'
	      (e.g.  `ah5') cause the check to be performed with months	(of 30
	      days), weeks, hours, minutes or seconds instead of days, respec-
	      tively.  An explicit `d' for days	is also	allowed.

	      Any  fractional  part  of	the difference between the access time
	      and the current part in the appropriate units is ignored in  the
	      comparison.   For	 instance,  `echo  *(ah-5)'  would  echo files
	      accessed within the last five hours, while `echo *(ah+5)'	 would
	      echo  files  accessed  at	least six hours	ago, as	times strictly
	      between five and six hours are treated as	five hours.

	      like the file access qualifier, except that  it  uses  the  file
	      modification time.

	      like  the	 file  access  qualifier, except that it uses the file
	      inode change time.

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

	      If this flag is directly followed	by a size specifier `k'	(`K'),
	      `m' (`M'), or `p'	(`P') (e.g. `Lk-50') the  check	 is  performed
	      with  kilobytes,	megabytes,  or	blocks (of 512 bytes) instead.
	      (On some systems additional specifiers are available  for	 giga-
	      bytes,  `g' or `G', and terabytes, `t' or	`T'.) If a size	speci-
	      fier is used a file is regarded as "exactly"  the	 size  if  the
	      file size	rounded	up to the next unit is equal to	the test size.
	      Hence `*(Lm1)' matches files from	1 byte up to 1 Megabyte	inclu-
	      sive.  Note also that the	set of files "less than" the test size
	      only includes files that would  not  match  the  equality	 test;
	      hence `*(Lm-1)' only matches files of zero size.

       ^      negates all qualifiers following it

       -      toggles  between	making	the  qualifiers	work on	symbolic links
	      (the default) and	the files they point to

       M      sets the MARK_DIRS option	for the	current	pattern

       T      appends a	trailing qualifier mark	to the filenames, analogous to
	      the LIST_TYPES option, for the current pattern (overrides	M)

       N      sets the NULL_GLOB option	for the	current	pattern

       D      sets the GLOB_DOTS option	for the	current	pattern

       n      sets the NUMERIC_GLOB_SORT option	for the	current	pattern

       Yn     enables short-circuit mode: the pattern will expand to at	most n
	      filenames.  If more than n  matches  exist,  only	 the  first  n
	      matches in directory traversal order will	be considered.

	      Implies oN when no oc qualifier is used.

       oc     specifies	how the	names of the files should be sorted. If	c is n
	      they are sorted by name; if it is	L they are sorted depending on
	      the size (length)	of the files; if l they	are sorted by the num-
	      ber of links; if a, m, or	c they are sorted by the time  of  the
	      last  access,  modification, or inode change respectively; if d,
	      files in subdirectories  appear  before  those  in  the  current
	      directory	 at  each level	of the search -- this is best combined
	      with other criteria, for example `odon' to  sort	on  names  for
	      files  within the	same directory;	if N, no sorting is performed.
	      Note that	a, m, and c compare the	age against the	current	 time,
	      hence the	first name in the list is the youngest file. Also note
	      that the modifiers ^ and - are used, so `*(^-oL)'	gives  a  list
	      of  all files sorted by file size	in descending order, following
	      any symbolic links.  Unless oN is	used,  multiple	 order	speci-
	      fiers may	occur to resolve ties.

	      The  default  sorting is n (by name) unless the Y	glob qualifier
	      is used, in which	case it	is N (unsorted).

	      oe and o+	are special cases; they	are  each  followed  by	 shell
	      code, delimited as for the e glob	qualifier and the + glob qual-
	      ifier respectively (see above).  The code	is executed  for  each
	      matched  file  with  the	parameter REPLY	set to the name	of the
	      file on entry and	globsort appended  to  zsh_eval_context.   The
	      code  should  modify  the	 parameter  REPLY in some fashion.  On
	      return, the value	of the parameter is used instead of  the  file
	      name  as	the string on which to sort.  Unlike other sort	opera-
	      tors, oe and o+ may be repeated, but note	that the maximum  num-
	      ber  of  sort  operators of any kind that	may appear in any glob
	      expression is 12.

       Oc     like `o',	but sorts in descending	order; i.e.  `*(^oc)'  is  the
	      same  as	`*(Oc)'	and `*(^Oc)' is	the same as `*(oc)'; `Od' puts
	      files in the current directory before those in subdirectories at
	      each level of the	search.

	      specifies	 which	of the matched filenames should	be included in
	      the returned list. The syntax is the  same  as  for  array  sub-
	      scripts.	beg  and  the optional end may be mathematical expres-
	      sions. As	in parameter subscripting they may be negative to make
	      them  count  from	 the  last match backward. E.g.: `*(-OL[1,3])'
	      gives a list of the names	of the three largest files.

	      The string will be prepended to each glob	match  as  a  separate
	      word.  string is delimited in the	same way as arguments to the e
	      glob qualifier described above.  The qualifier can be  repeated;
	      the words	are prepended separately so that the resulting command
	      line contains the	words in the same order	they were given	in the
	      list of glob qualifiers.

	      A	typical	use for	this is	to prepend an option before all	occur-
	      rences of	a file name; for example, the pattern `*(P:-f:)'  pro-
	      duces the	command	line arguments `-f file1 -f file2 ...'

	      If  the  modifier	 ^  is	active,	 then  string will be appended
	      instead of prepended.  Prepending	and appending is done indepen-
	      dently  so  both	can  be	 used on the same glob expression; for
	      example by writing `*(P:foo:^P:bar:^P:baz:)' which produces  the
	      command line arguments `foo baz file1 bar	...'

       More  than one of these lists can be combined, separated	by commas. The
       whole list matches if at	least one of the sublists  matches  (they  are
       `or'ed,	the qualifiers in the sublists are `and'ed).  Some qualifiers,
       however,	affect all matches generated, independent of  the  sublist  in
       which  they  are	 given.	  These	are the	qualifiers `M',	`T', `N', `D',
       `n', `o', `O' and the subscripts	given in brackets (`[...]').

       If a `:'	appears	in a qualifier list, the remainder of  the  expression
       in  parenthesis	is  interpreted	 as a modifier (see the	section	`Modi-
       fiers' in the section `History  Expansion').   Each  modifier  must  be
       introduced  by a	separate `:'.  Note also that the result after modifi-
       cation does not have to be an existing file.  The name of any  existing
       file  can  be  followed	by  a modifier of the form `(:...)' even if no
       actual filename generation is performed,	although note that  the	 pres-
       ence of the parentheses causes the entire expression to be subjected to
       any global pattern matching options such	as NULL_GLOB. Thus:

	      ls *(-/)

       lists all directories and symbolic links	that point to directories, and

	      ls *(-@)

       lists all broken	symbolic links,	and

	      ls *(%W)

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

	      ls *(W,X)

       lists  all  files  in  the current directory that are world-writable or
       world-executable, and

	      echo /tmp/foo*(u0^@:t)

       outputs the basename of all root-owned files beginning with the	string
       `foo' in	/tmp, ignoring symlinks, and

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

       lists  all  files  having a link	count of one whose names contain a dot
       (but not	those starting with  a	dot,  since  GLOB_DOTS	is  explicitly
       switched	off) except for	lex.c, lex.h, parse.c and parse.h.

	      print b*.pro(#q:s/pro/shmo/)(#q.:s/builtin/shmiltin/)

       demonstrates  how  colon	 modifiers and other qualifiers	may be chained
       together.  The ordinary qualifier `.' is	applied	first, then the	 colon
       modifiers  in order from	left to	right.	So if EXTENDED_GLOB is set and
       the base	pattern	matches	the regular file, the  shell  will
       print `shmiltin.shmo'.

zsh 5.3.1		       December	21, 2016		    ZSHEXPN(1)


Want to link to this manual page? Use this URL:

home | help