glob(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | CONFORMING TO | NOTES | BUGS | EXAMPLES | SEE ALSO | COLOPHON

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

NAME         top

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

SYNOPSIS         top

       #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         top

       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 pointers.

       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 character, 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
              character in the pattern, or an initial tilde is followed
              immediately by a slash ('/'), then the home directory of
              the caller is substituted 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
              difference is that if the username is invalid, or the home
              directory 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 interested 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), readdir(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 pointers 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
       invocations.

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

RETURN VALUE         top

       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         top

       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         top

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

NOTES         top

       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         top

       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.

EXAMPLES         top

       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         top

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

COLOPHON         top

       This page is part of release 5.10 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                            2020-06-09                        GLOB(3)

Pages that refer to this page: locate(1)tar(1)fnmatch(3)wordexp(3)glob(7)uri(7)