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GLOB(3)			   Linux Programmer's Manual		       GLOB(3)



NAME
       glob,  globfree	-  find pathnames matching a pattern, free memory from
       glob()

SYNOPSIS
       #include <glob.h>

       int glob(const char *pattern, int flags,
		int (*errfunc) (const char *epath, int eerrno),
		glob_t *pglob);
       void globfree(glob_t *pglob);

DESCRIPTION
       The glob() function searches for all  the  pathnames  matching  pattern
       according  to  the  rules  used	by  the shell (see glob(7)).  No tilde
       expansion or parameter substitution is done; if	you  want  these,  use
       wordexp(3).

       The globfree() function frees the dynamically allocated storage from an
       earlier call to glob().

       The results of a glob() call are stored in the structure pointed to  by
       pglob.	This  structure	 is  of type glob_t (declared in <glob.h>) and
       includes the following elements defined by POSIX.2 (more may be present
       as an extension):

	   typedef struct {
	       size_t	gl_pathc;    /* Count of paths matched so far  */
	       char   **gl_pathv;    /* List of matched pathnames.  */
	       size_t	gl_offs;     /* Slots to reserve in gl_pathv.  */
	   } glob_t;

       Results are stored in dynamically allocated storage.

       The  argument  flags  is	 made up of the bitwise OR of zero or more the
       following symbolic constants, which modify the behavior of glob():

       GLOB_ERR
	      Return upon a read error (because a directory does not have read
	      permission,  for example).  By default, glob() attempts carry on
	      despite errors, reading all of the directories that it can.

       GLOB_MARK
	      Append a slash to each path which corresponds to a directory.

       GLOB_NOSORT
	      Don't sort the returned pathnames.  The only reason to  do  this
	      is  to save processing time.  By default, the returned pathnames
	      are sorted.

       GLOB_DOOFFS
	      Reserve pglob->gl_offs slots at the beginning  of	 the  list  of
	      strings in pglob->pathv.	The reserved slots contain null point-
	      ers.

       GLOB_NOCHECK
	      If no pattern matches, return the original pattern.  By default,
	      glob() returns GLOB_NOMATCH if there are no matches.

       GLOB_APPEND
	      Append  the  results  of	this  call  to	the  vector of results
	      returned by a previous call to glob().  Do not set this flag  on
	      the first invocation of glob().

       GLOB_NOESCAPE
	      Don't  allow  backslash ('\') to be used as an escape character.
	      Normally, a backslash can be used to quote the following charac-
	      ter,  providing  a  mechanism  to	 turn  off the special meaning
	      metacharacters.

       flags may also include any of the following, which are  GNU  extensions
       and not defined by POSIX.2:

       GLOB_PERIOD
	      Allow  a	leading	 period	 to  be matched by metacharacters.  By
	      default, metacharacters can't match a leading period.

       GLOB_ALTDIRFUNC
	      Use alternative functions pglob->gl_closedir, pglob->gl_readdir,
	      pglob->gl_opendir,   pglob->gl_lstat,   and  pglob->gl_stat  for
	      filesystem access instead of the normal library functions.

       GLOB_BRACE
	      Expand csh(1) style brace expressions of the form {a,b}.	 Brace
	      expressions  can	be  nested.  Thus, for example, specifying the
	      pattern "{foo/{,cat,dog},bar}" would return the same results  as
	      four separate glob() calls using the strings: "foo/", "foo/cat",
	      "foo/dog", and "bar".

       GLOB_NOMAGIC
	      If the pattern contains no metacharacters,  then	it  should  be
	      returned	as  the	 sole  matching word, even if there is no file
	      with that name.

       GLOB_TILDE
	      Carry out tilde expansion.  If a tilde ('~') is the only charac-
	      ter  in the pattern, or an initial tilde is followed immediately
	      by a slash ('/'), then the home directory of the caller is  sub-
	      stituted	for  the  tilde.  If an initial tilde is followed by a
	      username (e.g., "~andrea/bin"), then the tilde and username  are
	      substituted by the home directory of that user.  If the username
	      is invalid, or the home directory cannot be determined, then  no
	      substitution is performed.

       GLOB_TILDE_CHECK
	      This  provides behavior similar to that of GLOB_TILDE.  The dif-
	      ference is that if the username is invalid, or the  home	direc-
	      tory  cannot  be	determined,  then instead of using the pattern
	      itself as the name, glob() returns GLOB_NOMATCH to  indicate  an
	      error.

       GLOB_ONLYDIR
	      This  is	a hint to glob() that the caller is interested only in
	      directories that match the pattern.  If the  implementation  can
	      easily  determine file-type information, then nondirectory files
	      are not returned to the caller.  However, the caller must	 still
	      check that returned files are directories.  (The purpose of this
	      flag is merely to optimize performance when the caller is inter-
	      ested only in directories.)

       If  errfunc is not NULL, it will be called in case of an error with the
       arguments epath, a pointer to the path which failed,  and  eerrno,  the
       value  of  errno as returned from one of the calls to opendir(3), read-
       dir(3), or stat(2).  If errfunc returns nonzero, or if GLOB_ERR is set,
       glob() will terminate after the call to errfunc.

       Upon  successful return, pglob->gl_pathc contains the number of matched
       pathnames and pglob->gl_pathv contains a pointer to the list of	point-
       ers to matched pathnames.  The list of pointers is terminated by a null
       pointer.

       It is possible to  call	glob()	several	 times.	  In  that  case,  the
       GLOB_APPEND flag has to be set in flags on the second and later invoca-
       tions.

       As a GNU extension, pglob->gl_flags is set to the flags specified, ored
       with GLOB_MAGCHAR if any metacharacters were found.

RETURN VALUE
       On  successful completion, glob() returns zero.	Other possible returns
       are:

       GLOB_NOSPACE
	      for running out of memory,

       GLOB_ABORTED
	      for a read error, and

       GLOB_NOMATCH
	      for no found matches.

ATTRIBUTES
       For  an	explanation  of	 the  terms  used   in	 this	section,   see
       attributes(7).

       +-----------+---------------+--------------------------+
       |Interface  | Attribute	   | Value		      |
       +-----------+---------------+--------------------------+
       |glob()	   | Thread safety | MT-Unsafe race:utent env |
       |	   |		   | sig:ALRM timer locale    |
       +-----------+---------------+--------------------------+
       |globfree() | Thread safety | MT-Safe		      |
       +-----------+---------------+--------------------------+
       In  the	above  table, utent in race:utent signifies that if any of the
       functions setutent(3), getutent(3), or endutent(3) are used in parallel
       in different threads of a program, then data races could occur.	glob()
       calls those functions, so we use race:utent to remind users.

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, POSIX.2.

NOTES
       The structure elements gl_pathc and gl_offs are declared as  size_t  in
       glibc  2.1, as they should be according to POSIX.2, but are declared as
       int in glibc 2.0.

BUGS
       The glob() function may fail due	 to  failure  of  underlying  function
       calls,  such  as malloc(3) or opendir(3).  These will store their error
       code in errno.

EXAMPLE
       One example of use is the following code, which simulates typing

	   ls -l *.c ../*.c

       in the shell:

	   glob_t globbuf;

	   globbuf.gl_offs = 2;
	   glob("*.c", GLOB_DOOFFS, NULL, &globbuf);
	   glob("../*.c", GLOB_DOOFFS | GLOB_APPEND, NULL, &globbuf);
	   globbuf.gl_pathv[0] = "ls";
	   globbuf.gl_pathv[1] = "-l";
	   execvp("ls", &globbuf.gl_pathv[0]);

SEE ALSO
       ls(1), sh(1),  stat(2),	exec(3),  fnmatch(3),  malloc(3),  opendir(3),
       readdir(3), wordexp(3), glob(7)

COLOPHON
       This  page  is  part of release 4.10 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest	  version     of     this    page,    can    be	   found    at
       https://www.kernel.org/doc/man-pages/.



GNU				  2016-10-08			       GLOB(3)