glob

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 ac-
       cording  to the rules used by the shell (see glob(7)).  No tilde expan-
       sion or parameter substitution is done; if you want  these,  use  word-
       exp(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 in-
       cludes 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 re-
              turned 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 de-
              fault, 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 re-
              turned  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 it-
              self as the name, glob() returns GLOB_NOMATCH to indicate an er-
              ror.

       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  at-
       tributes(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 5.05 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                               2019-03-06                           GLOB(3)