Computer Science
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 match-
ing 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, which is a glob_t which is declared
in <glob.h> and includes the following elements defined by
POSIX.2 (more may be present as a GNU extension):
typedef struct
{
int gl_pathc; /* Count of paths matched so far */
char **gl_pathv; /* List of matched pathnames. */
int gl_offs; /* Slots to reserve in `gl_pathv'. */
} glob_t;
Results are stored in dynamically allocated storage.
The parameter flags is made up of bitwise OR of zero or
more the following symbolic constants, which modify the of
behaviour of glob():
GLOB_ERR
which means to return upon read error (because a
directory does not have read permission, for exam-
ple),
GLOB_MARK
which means to append a slash to each path which
corresponds to a directory,
GLOB_NOSORT
which means don't sort the returned pathnames (they
are by default),
GLOB_DOOFS
which means that pglob->gl_offs slots will be
reserved at the beginning of the list of strings in
pglob->pathv,
GLOB_NOCHECK
which means that, if no pattern matches, to return
the original pattern,
GLOB_APPEND
which means to append to the results of a previous
call. Do not set this flag on the first invocation
of glob().
GLOB_NOESCAPE
which means that meta characters cannot be quoted
by backslashes.
The flags may also include some of the following, which
are GNU extensions and not defined by POSIX.2:
GLOB_PERIOD
which means that a leading period can be matched by
meta characters,
GLOB_ALTDIRFUNC
which means that alternative functions
pglob->gl_closedir, pglob->gl_readdir,
pglob->gl_opendir, pglob->gl_lstat, and
pglob->gl_stat are used for file system access
instead of the normal library functions,
GLOB_BRACE
which means that csh(1) style brace expresions
{a,b} are expanded,
GLOB_NOMAGIC
which means that the pattern is returned if it con-
tains no metacharacters,
GLOB_TILDE
which means that tilde expansion is carried out,
and
GLOB_ONLYDIR
which means that only directories are matched.
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(), readdir(), or stat().
If errfunc returns non-zero, or if GLOB_ERR is set, glob()
will terminate after the call to errfunc.
Upon successful return, pglob->gl_pathc contains the num-
ber of matched pathnames and pglob->gl_pathv a pointer to
the list of matched pathnames. The first pointer after
the last pathname is NULL.
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 VALUES
On successful completion, glob() returns zero. Other pos-
sible returns are:
GLOB_NOSPACE
for running out of memory,
GLOB_ABORTED
for a read error, and
GLOB_NOMATCH
for no found matches.
EXAMPLES
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_DOOFS, NULL, &globbuf);
glob("../*.c", GLOB_DOOFS | GLOB_APPEND, NULL, &globbuf);
globbuf.gl_pathv[0] = "ls";
globbuf.gl_pathv[1] = "-l";
execvp("ls", &globbuf.gl_pathv[0]);
CONFORMING TO
POSIX.2
BUGS
The glob() function may fail due to failure of underlying
function calls, such as malloc() or opendir(). These will
store their error code in errno.
The structure elements gl_pathc and gl_offs should be
declared as size_t, according to POSIX.2, but are declared
as int.
SEE ALSO
ls(1), sh(1), stat(2), exec(3), malloc(3), opendir(3),
readdir(3), wordexp(3), glob(7)
GNU 11 May 1998 1
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