[thirdparty/man-pages.git] / man3 / glob.3

.\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
.\"
.\" %%%LICENSE_START(VERBATIM)
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one.
.\"
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.  The author(s) may not
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
.\" professionally.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
.\" %%%LICENSE_END
.\"
.\" Modified Wed Jul 28 11:12:17 1993 by Rik Faith (faith@cs.unc.edu)
.\" Modified Mon May 13 23:08:50 1996 by Martin Schulze (joey@linux.de)
.\" Modified 11 May 1998 by Joseph S. Myers (jsm28@cam.ac.uk)
.\" Modified 990912 by aeb
.\" 2007-10-10 mtk
.\"     Added description of GLOB_TILDE_NOMATCH
.\"     Expanded the description of various flags
.\"     Various wording fixes.
.\"
.TH GLOB 3  2007-10-10 "GNU" "Linux Programmer's Manual"
.SH NAME
glob, globfree \- find pathnames matching a pattern, free memory from glob()
.SH SYNOPSIS
.nf
.B #include <glob.h>
.sp
.BI "int glob(const char *" pattern ", int " flags ,
.br
.BI "         int (*" errfunc ") (const char *" epath ", int " eerrno ),
.br
.BI "         glob_t *" pglob );
.br
.BI "void globfree(glob_t *" pglob );
.fi
.SH DESCRIPTION
The
.BR glob ()
function searches for all the pathnames matching
.I pattern
according to the rules used by the shell (see
.BR glob (7)).
No tilde expansion or parameter substitution is done; if you want
these, use
.BR wordexp (3).
.PP
The
.BR globfree ()
function frees the dynamically allocated storage from an earlier call
to
.BR glob ().
.PP
The results of a
.BR glob ()
call are stored in the structure pointed to by
.IR pglob .
This structure is of type
.I glob_t
(declared in
.IR <glob.h> )
and includes the following elements defined by POSIX.2 (more may be
present as an extension):
.PP
.br
.in +4n
.nf
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 \fIgl_pathv\fP.  */
} glob_t;
.fi
.in
.PP
Results are stored in dynamically allocated storage.
.PP
The argument
.I flags
is made up of the bitwise OR of zero or more the following symbolic
constants, which modify the behavior of
.BR glob ():
.TP
.B GLOB_ERR
Return upon a read error (because a directory does not
have read permission, for example).
By default,
.BR glob ()
attempts carry on despite errors,
reading all of the directories that it can.
.TP
.B GLOB_MARK
Append a slash to each path which corresponds to a directory.
.TP
.B 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.
.TP
.B GLOB_DOOFFS
Reserve
.I pglob\->gl_offs
slots at the beginning of the list of strings in
.IR pglob\->pathv .
The reserved slots contain NULL pointers.
.TP
.B GLOB_NOCHECK
If no pattern matches, return the original pattern.
By default,
.BR glob ()
returns
.B GLOB_NOMATCH
if there are no matches.
.TP
.B GLOB_APPEND
Append the results of this call to the vector of results
returned by a previous call to
.BR glob ().
Do not set this flag on the first invocation of
.BR glob ().
.TP
.B GLOB_NOESCAPE
Don't allow backslash (\(aq\\\(aq) 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.
.PP
.I flags
may also include any of the following, which are GNU
extensions and not defined by POSIX.2:
.TP
.B GLOB_PERIOD
Allow a leading period to be matched by metacharacters.
By default, metacharacters can't match a leading period.
.TP
.B GLOB_ALTDIRFUNC
Use alternative functions
.IR pglob\->gl_closedir ,
.IR pglob\->gl_readdir ,
.IR pglob\->gl_opendir ,
.IR pglob\->gl_lstat ", and"
.I pglob\->gl_stat
for file system access instead of the normal library
functions.
.TP
.B GLOB_BRACE
Expand
.BR csh (1)
style brace expressions of the form \fB{a,b}\fR.
Brace expressions can be nested.
Thus, for example, specifying the pattern
"{foo/{,cat,dog},bar}" would return the same results as four separate
.BR glob ()
calls using the strings:
"foo/",
"foo/cat",
"foo/dog",
and
"bar".
.TP
.B 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.
.TP
.B GLOB_TILDE
Carry out tilde expansion.
If a tilde (\(aq~\(aq) is the only character in the pattern,
or an initial tilde is followed immediately by a slash (\(aq/\(aq),
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.
.TP
.B GLOB_TILDE_CHECK
This provides behavior similar to that of
.BR 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,
.BR glob ()
returns
.BR GLOB_NOMATCH
to indicate an error.
.TP
.B GLOB_ONLYDIR
This is a
.I hint
to
.BR 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.)
.PP
If
.I errfunc
is not NULL,
it will be called in case of an error with the arguments
.IR epath ,
a pointer to the path which failed, and
.IR eerrno ,
the value of
.I errno
as returned from one of the calls to
.BR opendir (3),
.BR readdir (3),
or
.BR stat (2).
If
.I errfunc
returns nonzero, or if
.B GLOB_ERR
is set,
.BR glob ()
will terminate after the call to
.IR errfunc .
.PP
Upon successful return,
.I pglob\->gl_pathc
contains the number of matched pathnames and
.I pglob\->gl_pathv
contains a pointer to the list of pointers to matched pathnames.
The list of pointers is terminated by a NULL pointer.
.PP
It is possible to call
.BR glob ()
several times.
In that case, the
.B GLOB_APPEND
flag has to be set in
.I flags
on the second and later invocations.
.PP
As a GNU extension,
.I pglob\->gl_flags
is set to the flags specified, \fBor\fRed with
.B GLOB_MAGCHAR
if any metacharacters were found.
.SH RETURN VALUE
On successful completion,
.BR glob ()
returns zero.
Other possible returns are:
.TP
.B GLOB_NOSPACE
for running out of memory,
.TP
.B GLOB_ABORTED
for a read error, and
.TP
.B GLOB_NOMATCH
for no found matches.
.SH CONFORMING TO
POSIX.2, POSIX.1-2001.
.SH NOTES
The structure elements
.I gl_pathc
and
.I gl_offs
are declared as
.I size_t
in glibc 2.1, as they should be according to POSIX.2,
but are declared as
.I int
in libc4, libc5 and glibc 2.0.
.SH BUGS
The
.BR glob ()
function may fail due to failure of underlying function calls, such as
.BR malloc (3)
or
.BR opendir (3).
These will store their error code in
.IR errno .
.SH EXAMPLE
One example of use is the following code, which simulates typing
.sp
.in +4n
ls \-l *.c ../*.c
.in
.sp
in the shell:
.nf
.in +4n

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]);
.in
.fi
.SH SEE ALSO
.BR ls (1),
.BR sh (1),
.BR stat (2),
.BR exec (3),
.BR fnmatch (3),
.BR malloc (3),
.BR opendir (3),
.BR readdir (3),
.BR wordexp (3),
.BR glob (7)
Commit	Line	Data
	1	.\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
	2	.\"
	3	.\" %%%LICENSE_START(VERBATIM)
	4	.\" Permission is granted to make and distribute verbatim copies of this
	5	.\" manual provided the copyright notice and this permission notice are
	6	.\" preserved on all copies.
	7	.\"
	8	.\" Permission is granted to copy and distribute modified versions of this
	9	.\" manual under the conditions for verbatim copying, provided that the
	10	.\" entire resulting derived work is distributed under the terms of a
	11	.\" permission notice identical to this one.
	12	.\"
	13	.\" Since the Linux kernel and libraries are constantly changing, this
	14	.\" manual page may be incorrect or out-of-date. The author(s) assume no
	15	.\" responsibility for errors or omissions, or for damages resulting from
	16	.\" the use of the information contained herein. The author(s) may not
	17	.\" have taken the same level of care in the production of this manual,
	18	.\" which is licensed free of charge, as they might when working
	19	.\" professionally.
	20	.\"
	21	.\" Formatted or processed versions of this manual, if unaccompanied by
	22	.\" the source, must acknowledge the copyright and authors of this work.
	23	.\" %%%LICENSE_END
	24	.\"
	25	.\" Modified Wed Jul 28 11:12:17 1993 by Rik Faith (faith@cs.unc.edu)
	26	.\" Modified Mon May 13 23:08:50 1996 by Martin Schulze (joey@linux.de)
	27	.\" Modified 11 May 1998 by Joseph S. Myers (jsm28@cam.ac.uk)
	28	.\" Modified 990912 by aeb
	29	.\" 2007-10-10 mtk
	30	.\" Added description of GLOB_TILDE_NOMATCH
	31	.\" Expanded the description of various flags
	32	.\" Various wording fixes.
	33	.\"
	34	.TH GLOB 3 2007-10-10 "GNU" "Linux Programmer's Manual"
	35	.SH NAME
	36	glob, globfree \- find pathnames matching a pattern, free memory from glob()
	37	.SH SYNOPSIS
	38	.nf
	39	.B #include <glob.h>
	40	.sp
	41	.BI "int glob(const char *" pattern ", int " flags ,
	42	.br
	43	.BI " int (" errfunc ") (const char " epath ", int " eerrno ),
	44	.br
	45	.BI " glob_t *" pglob );
	46	.br
	47	.BI "void globfree(glob_t *" pglob );
	48	.fi
	49	.SH DESCRIPTION
	50	The
	51	.BR glob ()
	52	function searches for all the pathnames matching
	53	.I pattern
	54	according to the rules used by the shell (see
	55	.BR glob (7)).
	56	No tilde expansion or parameter substitution is done; if you want
	57	these, use
	58	.BR wordexp (3).
	59	.PP
	60	The
	61	.BR globfree ()
	62	function frees the dynamically allocated storage from an earlier call
	63	to
	64	.BR glob ().
	65	.PP
	66	The results of a
	67	.BR glob ()
	68	call are stored in the structure pointed to by
	69	.IR pglob .
	70	This structure is of type
	71	.I glob_t
	72	(declared in
	73	.IR <glob.h> )
	74	and includes the following elements defined by POSIX.2 (more may be
	75	present as an extension):
	76	.PP
	77	.br
	78	.in +4n
	79	.nf
	80	typedef struct {
	81	size_t gl_pathc; /* Count of paths matched so far */
	82	char *gl_pathv; / List of matched pathnames. */
	83	size_t gl_offs; /* Slots to reserve in \fIgl_pathv\fP. */
	84	} glob_t;
	85	.fi
	86	.in
	87	.PP
	88	Results are stored in dynamically allocated storage.
	89	.PP
	90	The argument
	91	.I flags
	92	is made up of the bitwise OR of zero or more the following symbolic
	93	constants, which modify the behavior of
	94	.BR glob ():
	95	.TP
	96	.B GLOB_ERR
	97	Return upon a read error (because a directory does not
	98	have read permission, for example).
	99	By default,
	100	.BR glob ()
	101	attempts carry on despite errors,
	102	reading all of the directories that it can.
	103	.TP
	104	.B GLOB_MARK
	105	Append a slash to each path which corresponds to a directory.
	106	.TP
	107	.B GLOB_NOSORT
	108	Don't sort the returned pathnames.
	109	The only reason to do this is to save processing time.
	110	By default, the returned pathnames are sorted.
	111	.TP
	112	.B GLOB_DOOFFS
	113	Reserve
	114	.I pglob\->gl_offs
	115	slots at the beginning of the list of strings in
	116	.IR pglob\->pathv .
	117	The reserved slots contain NULL pointers.
	118	.TP
	119	.B GLOB_NOCHECK
	120	If no pattern matches, return the original pattern.
	121	By default,
	122	.BR glob ()
	123	returns
	124	.B GLOB_NOMATCH
	125	if there are no matches.
	126	.TP
	127	.B GLOB_APPEND
	128	Append the results of this call to the vector of results
	129	returned by a previous call to
	130	.BR glob ().
	131	Do not set this flag on the first invocation of
	132	.BR glob ().
	133	.TP
	134	.B GLOB_NOESCAPE
	135	Don't allow backslash (\(aq\\\(aq) to be used as an escape
	136	character.
	137	Normally, a backslash can be used to quote the following character,
	138	providing a mechanism to turn off the special meaning
	139	metacharacters.
	140	.PP
	141	.I flags
	142	may also include any of the following, which are GNU
	143	extensions and not defined by POSIX.2:
	144	.TP
	145	.B GLOB_PERIOD
	146	Allow a leading period to be matched by metacharacters.
	147	By default, metacharacters can't match a leading period.
	148	.TP
	149	.B GLOB_ALTDIRFUNC
	150	Use alternative functions
	151	.IR pglob\->gl_closedir ,
	152	.IR pglob\->gl_readdir ,
	153	.IR pglob\->gl_opendir ,
	154	.IR pglob\->gl_lstat ", and"
	155	.I pglob\->gl_stat
	156	for file system access instead of the normal library
	157	functions.
	158	.TP
	159	.B GLOB_BRACE
	160	Expand
	161	.BR csh (1)
	162	style brace expressions of the form \fB{a,b}\fR.
	163	Brace expressions can be nested.
	164	Thus, for example, specifying the pattern
	165	"{foo/{,cat,dog},bar}" would return the same results as four separate
	166	.BR glob ()
	167	calls using the strings:
	168	"foo/",
	169	"foo/cat",
	170	"foo/dog",
	171	and
	172	"bar".
	173	.TP
	174	.B GLOB_NOMAGIC
	175	If the pattern contains no metacharacters
	176	then it should be returned as the sole matching word,
	177	even if there is no file with that name.
	178	.TP
	179	.B GLOB_TILDE
	180	Carry out tilde expansion.
	181	If a tilde (\(aq~\(aq) is the only character in the pattern,
	182	or an initial tilde is followed immediately by a slash (\(aq/\(aq),
	183	then the home directory of the caller is substituted for
	184	the tilde.
	185	If an initial tilde is followed by a username (e.g., "~andrea/bin"),
	186	then the tilde and username are substituted by the home directory
	187	of that user.
	188	If the username is invalid, or the home directory cannot be
	189	determined, then no substitution is performed.
	190	.TP
	191	.B GLOB_TILDE_CHECK
	192	This provides behavior similar to that of
	193	.BR GLOB_TILDE .
	194	The difference is that if the username is invalid, or the
	195	home directory cannot be determined, then
	196	instead of using the pattern itself as the name,
	197	.BR glob ()
	198	returns
	199	.BR GLOB_NOMATCH
	200	to indicate an error.
	201	.TP
	202	.B GLOB_ONLYDIR
	203	This is a
	204	.I hint
	205	to
	206	.BR glob ()
	207	that the caller is interested only in directories that match the pattern.
	208	If the implementation can easily determine file-type information,
	209	then nondirectory files are not returned to the caller.
	210	However, the caller must still check that returned files
	211	are directories.
	212	(The purpose of this flag is merely to optimize performance when
	213	the caller is interested only in directories.)
	214	.PP
	215	If
	216	.I errfunc
	217	is not NULL,
	218	it will be called in case of an error with the arguments
	219	.IR epath ,
	220	a pointer to the path which failed, and
	221	.IR eerrno ,
	222	the value of
	223	.I errno
	224	as returned from one of the calls to
	225	.BR opendir (3),
	226	.BR readdir (3),
	227	or
	228	.BR stat (2).
	229	If
	230	.I errfunc
	231	returns nonzero, or if
	232	.B GLOB_ERR
	233	is set,
	234	.BR glob ()
	235	will terminate after the call to
	236	.IR errfunc .
	237	.PP
	238	Upon successful return,
	239	.I pglob\->gl_pathc
	240	contains the number of matched pathnames and
	241	.I pglob\->gl_pathv
	242	contains a pointer to the list of pointers to matched pathnames.
	243	The list of pointers is terminated by a NULL pointer.
	244	.PP
	245	It is possible to call
	246	.BR glob ()
	247	several times.
	248	In that case, the
	249	.B GLOB_APPEND
	250	flag has to be set in
	251	.I flags
	252	on the second and later invocations.
	253	.PP
	254	As a GNU extension,
	255	.I pglob\->gl_flags
	256	is set to the flags specified, \fBor\fRed with
	257	.B GLOB_MAGCHAR
	258	if any metacharacters were found.
	259	.SH RETURN VALUE
	260	On successful completion,
	261	.BR glob ()
	262	returns zero.
	263	Other possible returns are:
	264	.TP
	265	.B GLOB_NOSPACE
	266	for running out of memory,
	267	.TP
	268	.B GLOB_ABORTED
	269	for a read error, and
	270	.TP
	271	.B GLOB_NOMATCH
	272	for no found matches.
	273	.SH CONFORMING TO
	274	POSIX.2, POSIX.1-2001.
	275	.SH NOTES
	276	The structure elements
	277	.I gl_pathc
	278	and
	279	.I gl_offs
	280	are declared as
	281	.I size_t
	282	in glibc 2.1, as they should be according to POSIX.2,
	283	but are declared as
	284	.I int
	285	in libc4, libc5 and glibc 2.0.
	286	.SH BUGS
	287	The
	288	.BR glob ()
	289	function may fail due to failure of underlying function calls, such as
	290	.BR malloc (3)
	291	or
	292	.BR opendir (3).
	293	These will store their error code in
	294	.IR errno .
	295	.SH EXAMPLE
	296	One example of use is the following code, which simulates typing
	297	.sp
	298	.in +4n
	299	ls \-l .c ../.c
	300	.in
	301	.sp
	302	in the shell:
	303	.nf
	304	.in +4n
	305
	306	glob_t globbuf;
	307
	308	globbuf.gl_offs = 2;
	309	glob("*.c", GLOB_DOOFFS, NULL, &globbuf);
	310	glob("../*.c", GLOB_DOOFFS \| GLOB_APPEND, NULL, &globbuf);
	311	globbuf.gl_pathv[0] = "ls";
	312	globbuf.gl_pathv[1] = "\-l";
	313	execvp("ls", &globbuf.gl_pathv[0]);
	314	.in
	315	.fi
	316	.SH SEE ALSO
	317	.BR ls (1),
	318	.BR sh (1),
	319	.BR stat (2),
	320	.BR exec (3),
	321	.BR fnmatch (3),
	322	.BR malloc (3),
	323	.BR opendir (3),
	324	.BR readdir (3),
	325	.BR wordexp (3),
	326	.BR glob (7)