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NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | STANDARDS | HISTORY | NOTES | BUGS | EXAMPLES | SEE ALSO | COLOPHON |
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glob(3) Library Functions Manual glob(3)
glob, globfree - find pathnames matching a pattern, free memory
from glob()
Standard C library (libc, -lc)
#include <glob.h>
int glob(const char *restrict pattern, int flags,
int (*errfunc)(const char *epath, int eerrno),
glob_t *restrict pglob);
void globfree(glob_t *pglob);
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.
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.
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.
POSIX.1-2008.
POSIX.1-2001, POSIX.2.
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.
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.
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]);
ls(1), sh(1), stat(2), exec(3), fnmatch(3), malloc(3),
opendir(3), readdir(3), wordexp(3), glob(7)
This page is part of the man-pages (Linux kernel and C library
user-space interface documentation) project. Information about
the project can be found at
⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report
for this manual page, see
⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
This page was obtained from the tarball man-pages-6.9.1.tar.gz
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⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
2024-06-26. If you discover any rendering problems in this HTML
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man-pages@man7.org
Linux man-pages 6.9.1 2024-06-15 glob(3)
Pages that refer to this page: locate(1), tar(1), fnmatch(3), wordexp(3), glob(7), pcilib(7), uri(7)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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