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GLOB(3)                FreeBSD Library Functions Manual                GLOB(3)

NAME
     glob, globfree -- generate pathnames matching a pattern

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <glob.h>

     int
     glob(const char *pattern, int flags, int (*errfunc)(const char *, int),
         glob_t *pglob);

     void
     globfree(glob_t *pglob);

DESCRIPTION
     The glob() function is a pathname generator that implements the rules for
     file name pattern matching used by the shell.

     The include file <glob.h> defines the structure type glob_t, which con-
     tains at least the following fields:

     typedef struct {
             int gl_pathc;           /* count of total paths so far */
             int gl_matchc;          /* count of paths matching pattern */
             int gl_offs;            /* reserved at beginning of gl_pathv */
             int gl_flags;           /* returned flags */
             char **gl_pathv;        /* list of paths matching pattern */
     } glob_t;

     The argument pattern is a pointer to a pathname pattern to be expanded.
     The glob() argument matches all accessible pathnames against the pattern
     and creates a list of the pathnames that match.  In order to have access
     to a pathname, glob() requires search permission on every component of a
     path except the last and read permission on each directory of any file-
     name component of pattern that contains any of the special characters
     `*', `?' or `['.

     The glob() argument stores the number of matched pathnames into the
     gl_pathc field, and a pointer to a list of pointers to pathnames into the
     gl_pathv field.  The first pointer after the last pathname is NULL.  If
     the pattern does not match any pathnames, the returned number of matched
     paths is set to zero.

     It is the caller's responsibility to create the structure pointed to by
     pglob.  The glob() function allocates other space as needed, including
     the memory pointed to by gl_pathv.

     The argument flags is used to modify the behavior of glob().  The value
     of flags is the bitwise inclusive OR of any of the following values
     defined in <glob.h>:

     GLOB_APPEND      Append pathnames generated to the ones from a previous
                      call (or calls) to glob().  The value of gl_pathc will
                      be the total matches found by this call and the previous
                      call(s).  The pathnames are appended to, not merged with
                      the pathnames returned by the previous call(s).  Between
                      calls, the caller must not change the setting of the
                      GLOB_DOOFFS flag, nor change the value of gl_offs when
                      GLOB_DOOFFS is set, nor (obviously) call globfree() for
                      pglob.

     GLOB_DOOFFS      Make use of the gl_offs field.  If this flag is set,
                      gl_offs is used to specify how many NULL pointers to
                      prepend to the beginning of the gl_pathv field.  In
                      other words, gl_pathv will point to gl_offs NULL point-
                      ers, followed by gl_pathc pathname pointers, followed by
                      a NULL pointer.

     GLOB_ERR         Causes glob() to return when it encounters a directory
                      that it cannot open or read.  Ordinarily, glob() contin-
                      ues to find matches.

     GLOB_MARK        Each pathname that is a directory that matches pattern
                      has a slash appended.

     GLOB_NOCHECK     If pattern does not match any pathname, then glob()
                      returns a list consisting of only pattern, with the num-
                      ber of total pathnames set to 1, and the number of
                      matched pathnames set to 0.  The effect of backslash
                      escaping is present in the pattern returned.

     GLOB_NOESCAPE    By default, a backslash (`\') character is used to
                      escape the following character in the pattern, avoiding
                      any special interpretation of the character.  If
                      GLOB_NOESCAPE is set, backslash escaping is disabled.

     GLOB_NOSORT      By default, the pathnames are sorted in ascending ASCII
                      order; this flag prevents that sorting (speeding up
                      glob()).

     The following values may also be included in flags, however, they are
     non-standard extensions to IEEE Std 1003.2 (``POSIX.2'').

     GLOB_ALTDIRFUNC  The following additional fields in the pglob structure
                      have been initialized with alternate functions for glob
                      to use to open, read, and close directories and to get
                      stat information on names found in those directories.

                      void *(*gl_opendir)(const char * name);
                      struct dirent *(*gl_readdir)(void *);
                      void (*gl_closedir)(void *);
                      int (*gl_lstat)(const char *name, struct stat *st);
                      int (*gl_stat)(const char *name, struct stat *st);

                      This extension is provided to allow programs such as
                      restore(8) to provide globbing from directories stored
                      on tape.

     GLOB_BRACE       Pre-process the pattern string to expand `{pat,pat,...}'
                      strings like csh(1).  The pattern `{}' is left unex-
                      panded for historical reasons (and csh(1) does the same
                      thing to ease typing of find(1) patterns).

     GLOB_MAGCHAR     Set by the glob() function if the pattern included glob-
                      bing characters.  See the description of the usage of
                      the gl_matchc structure member for more details.

     GLOB_NOMAGIC     Is the same as GLOB_NOCHECK but it only appends the
                      pattern if it does not contain any of the special char-
                      acters ``*'', ``?'' or ``[''.  GLOB_NOMAGIC is provided
                      to simplify implementing the historic csh(1) globbing
                      behavior and should probably not be used anywhere else.

     GLOB_TILDE       Expand patterns that start with `~' to user name home
                      directories.

     GLOB_LIMIT       Limit the total number of returned pathnames to the
                      value provided in gl_matchc (default ARG_MAX).  This
                      option should be set for programs that can be coerced
                      into a denial of service attack via patterns that expand
                      to a very large number of matches, such as a long string
                      of `*/../*/..'.

     If, during the search, a directory is encountered that cannot be opened
     or read and errfunc is non-NULL, glob() calls (*errfunc)(path, errno).
     This may be unintuitive: a pattern like `*/Makefile' will try to stat(2)
     `foo/Makefile' even if `foo' is not a directory, resulting in a call to
     errfunc.  The error routine can suppress this action by testing for
     ENOENT and ENOTDIR; however, the GLOB_ERR flag will still cause an imme-
     diate return when this happens.

     If errfunc returns non-zero, glob() stops the scan and returns
     GLOB_ABORTED after setting gl_pathc and gl_pathv to reflect any paths
     already matched.  This also happens if an error is encountered and
     GLOB_ERR is set in flags, regardless of the return value of errfunc, if
     called.  If GLOB_ERR is not set and either errfunc is NULL or errfunc
     returns zero, the error is ignored.

     The globfree() function frees any space associated with pglob from a pre-
     vious call(s) to glob().

RETURN VALUES
     On successful completion, glob() returns zero.  In addition the fields of
     pglob contain the values described below:

     gl_pathc      contains the total number of matched pathnames so far.
                   This includes other matches from previous invocations of
                   glob() if GLOB_APPEND was specified.

     gl_matchc     contains the number of matched pathnames in the current
                   invocation of glob().

     gl_flags      contains a copy of the flags argument with the bit
                   GLOB_MAGCHAR set if pattern contained any of the special
                   characters ``*'', ``?'' or ``['', cleared if not.

     gl_pathv      contains a pointer to a NULL-terminated list of matched
                   pathnames.  However, if gl_pathc is zero, the contents of
                   gl_pathv are undefined.

     If glob() terminates due to an error, it sets errno and returns one of
     the following non-zero constants, which are defined in the include file
     <glob.h>:

     GLOB_NOSPACE  An attempt to allocate memory failed, or if errno was 0
                   GLOB_LIMIT was specified in the flags and pglob-_gl_matchc
                   or more patterns were matched.

     GLOB_ABORTED  The scan was stopped because an error was encountered and
                   either GLOB_ERR was set or (*errfunc)() returned non-zero.

     GLOB_NOMATCH  The pattern did not match a pathname and GLOB_NOCHECK was
                   not set.

     The arguments pglob-_gl_pathc and pglob-_gl_pathv are still set as speci-
     fied above.

EXAMPLES
     A rough equivalent of `ls -l *.c *.h' can be obtained with the following
     code:

           glob_t g;

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

SEE ALSO
     sh(1), fnmatch(3), regexp(3)

STANDARDS
     The current implementation of the glob() function does not conform to
     IEEE Std 1003.2 (``POSIX.2'').  Collating symbol expressions, equivalence
     class expressions and character class expressions are not supported.

     The flags GLOB_ALTDIRFUNC, GLOB_BRACE, GLOB_LIMIT, GLOB_MAGCHAR,
     GLOB_NOMAGIC, and GLOB_TILDE, and the fields gl_matchc and gl_flags are
     extensions to the POSIX standard and should not be used by applications
     striving for strict conformance.

HISTORY
     The glob() and globfree() functions first appeared in 4.4BSD.

BUGS
     Patterns longer than MAXPATHLEN may cause unchecked errors.

     The glob() argument may fail and set errno for any of the errors speci-
     fied for the library routines stat(2), closedir(3), opendir(3),
     readdir(3), malloc(3), and free(3).

FreeBSD 6.2                    September 1, 2004                   FreeBSD 6.2

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | EXAMPLES | SEE ALSO | STANDARDS | HISTORY | BUGS

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