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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | CONFORMING TO | NOTES | BUGS | EXAMPLE | SEE ALSO | COLOPHON |
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GLOB(3) Linux Programmer's Manual GLOB(3)
glob, globfree - find pathnames matching a pattern, free memory from
glob()
#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);
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 path‐
names 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 char‐
acter, 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_read‐
dir, 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, specify‐
ing 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 char‐
acter in the pattern, or an initial tilde is followed immedi‐
ately 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 user‐
name 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 pat‐
tern itself as the name, glob() returns GLOB_NOMATCH to indi‐
cate 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 invo‐
cations.
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.1-2001, POSIX.1-2008, 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 release 4.15 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 2017-09-15 GLOB(3)
Pages that refer to this page: locate(1), tar(1), fnmatch(3), wordexp(3), glob(7), uri(7)
Copyright and license for this manual page
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