GLOB(3) | Library Functions Manual | GLOB(3) |
glob
, globfree
,
glob_pattern_p
—
#include <glob.h>
int
glob
(const
char * restrict pattern,
int flags,
int (*errfunc)(const char *,
int), glob_t * restrict
pglob);
void
globfree
(glob_t
*pglob);
int
glob_pattern_p
(const
char *pattern, int
quote);
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 contains at least the following fields:
typedef struct { size_t gl_pathc; /* count of total paths so far */ size_t gl_matchc; /* count of paths matching pattern */ size_t 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
filename 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
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
NULL
pointers to prepend to the beginning of the
gl_pathv field. In other words,
gl_pathv will point to gl_offs
NULL
pointers, followed by
gl_pathc pathname pointers, followed by a
NULL
pointer.GLOB_ERR
glob
() to return when it encounters a
directory that it cannot open or read. Ordinarily,
glob
() continues to find matches.GLOB_MARK
GLOB_NOCHECK
glob
() returns a list consisting of only
pattern, with one level of backslash escapes
removed, the number of total pathnames set to 1, and the number of matched
pathnames set to 0.GLOB_NOSORT
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
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
{pat,pat,...}
’ strings like
csh(1). The pattern
‘{}
’ is left unexpanded for
historical reasons (csh(1) does
the same thing to ease typing of
find(1) patterns).GLOB_LIMIT
64K
, the number of
stat(2) calls to 128, and the
number of readdir(3) calls
to 16K. This option should be set for programs that can be coerced to a
denial of service attack via patterns that expand to a very large number
of matches, such as a long string of
*/../*/..
GLOB_MAGCHAR
glob
() function if the pattern included
globbing characters. See the description of the usage of the
gl_matchc structure member for more details.GLOB_NOESCAPE
\
’) character for quoting.GLOB_NOMAGIC
GLOB_NOCHECK
but it only appends
the pattern if it does not contain any of the
special characters ``*'', ``?'' or ``[''.
GLOB_NOMAGIC
is provided to simplify implementing
the historic csh(1) globbing
behavior and should probably not be used anywhere else.GLOB_NO_DOTDIRS
.
’ and
‘..
’ from metacharacter matches,
regardless of whether GLOB_PERIOD
is set and
whether the pattern component begins with a literal period.GLOB_PERIOD
GLOB_STAR
*
characters will do a
recursive match in all subdirs, without following symbolic links and three
adjacent *
characters will also follow symbolic
links.GLOB_TILDE
~
’
to user name home directories. If the user with the given user name (or
the user id of the current user in the case of “~/”) is not
found, the original pattern is returned.GLOB_TILDE_CHECK
GLOB_TILDE
and the user name or the
user id is not found, then GLOB_NOMATCH
is
returned instead of the original pattern.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 immediate 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 previous call(s) to
glob
().
The glob_pattern_p
() returns
1
if the pattern has any
special characters that glob
() will interpret and
0
otherwise. If the quote
argument is non-zero, then backslash quoted characters are ignored.
The historical GLOB_QUOTE
flag is no
longer supported. Per IEEE Std 1003.2-1992
(“POSIX.2”), backslash escaping of special characters
is the default behaviour; it may be disabled by specifying the
GLOB_NOESCAPE
flag.
glob
() returns zero. In
addition the fields of pglob contain the values
described below:
glob
() if
GLOB_APPEND
was specified.glob
().GLOB_MAGCHAR
set if pattern
contained any of the special characters ``*'', ``?'' or ``['', cleared if
not.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_ABORTED
GLOB_ERR
was set or
(*errfunc)() returned non-zero.GLOB_NOMATCH
GLOB_NOCHECK
was not set in
flags
.GLOB_NOSPACE
GLOB_LIMIT
was specified in the flags and
ARG_MAX
patterns were matched.The historical GLOB_ABEND
return constant
is no longer supported. Portable applications should use the
GLOB_ABORTED
constant instead.
The arguments pglob->gl_pathc and pglob->gl_pathv are still set as specified above.
HOME
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);
glob
() function is expected to be
IEEE Std 1003.2 (“POSIX.2”) compatible
with the exception that the flags GLOB_ALTDIRFUNC
,
GLOB_BRACE
, GLOB_LIMIT
,
GLOB_MAGCHAR
, GLOB_NOESCAPE
,
GLOB_NOMAGIC
, GLOB_NO_DOTDIRS
,
GLOB_PERIOD
, GLOB_STAR
,
GLOB_TILDE
, and the fields
gl_matchc and gl_flags should not
be used by applications striving for strict POSIX conformance.
glob
() and globfree
()
functions first appeared in 4.4BSD. The
glob_pattern_p
() function is modelled after the one
found in glibc.
MAXPATHLEN
may cause unchecked
errors.
The glob
() function may fail and set
errno for any of the errors specified for the library
routines stat(2),
closedir(3),
opendir(3),
readdir(3),
malloc(3), and
free(3).
May 28, 2019 | NetBSD 9.2 |