1glob(3) Library Functions Manual glob(3)
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6 glob, globfree - find pathnames matching a pattern, free memory from
7 glob()
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10 Standard C library (libc, -lc)
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13 #include <glob.h>
14
15 int glob(const char *restrict pattern, int flags,
16 int (*errfunc)(const char *epath, int eerrno),
17 glob_t *restrict pglob);
18 void globfree(glob_t *pglob);
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21 The glob() function searches for all the pathnames matching pattern ac‐
22 cording to the rules used by the shell (see glob(7)). No tilde expan‐
23 sion or parameter substitution is done; if you want these, use word‐
24 exp(3).
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26 The globfree() function frees the dynamically allocated storage from an
27 earlier call to glob().
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29 The results of a glob() call are stored in the structure pointed to by
30 pglob. This structure is of type glob_t (declared in <glob.h>) and in‐
31 cludes the following elements defined by POSIX.2 (more may be present
32 as an extension):
33
34 typedef struct {
35 size_t gl_pathc; /* Count of paths matched so far */
36 char **gl_pathv; /* List of matched pathnames. */
37 size_t gl_offs; /* Slots to reserve in gl_pathv. */
38 } glob_t;
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40 Results are stored in dynamically allocated storage.
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42 The argument flags is made up of the bitwise OR of zero or more the
43 following symbolic constants, which modify the behavior of glob():
44
45 GLOB_ERR
46 Return upon a read error (because a directory does not have read
47 permission, for example). By default, glob() attempts carry on
48 despite errors, reading all of the directories that it can.
49
50 GLOB_MARK
51 Append a slash to each path which corresponds to a directory.
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53 GLOB_NOSORT
54 Don't sort the returned pathnames. The only reason to do this
55 is to save processing time. By default, the returned pathnames
56 are sorted.
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58 GLOB_DOOFFS
59 Reserve pglob->gl_offs slots at the beginning of the list of
60 strings in pglob->pathv. The reserved slots contain null point‐
61 ers.
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63 GLOB_NOCHECK
64 If no pattern matches, return the original pattern. By default,
65 glob() returns GLOB_NOMATCH if there are no matches.
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67 GLOB_APPEND
68 Append the results of this call to the vector of results re‐
69 turned by a previous call to glob(). Do not set this flag on
70 the first invocation of glob().
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72 GLOB_NOESCAPE
73 Don't allow backslash ('\') to be used as an escape character.
74 Normally, a backslash can be used to quote the following charac‐
75 ter, providing a mechanism to turn off the special meaning
76 metacharacters.
77
78 flags may also include any of the following, which are GNU extensions
79 and not defined by POSIX.2:
80
81 GLOB_PERIOD
82 Allow a leading period to be matched by metacharacters. By de‐
83 fault, metacharacters can't match a leading period.
84
85 GLOB_ALTDIRFUNC
86 Use alternative functions pglob->gl_closedir, pglob->gl_readdir,
87 pglob->gl_opendir, pglob->gl_lstat, and pglob->gl_stat for
88 filesystem access instead of the normal library functions.
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90 GLOB_BRACE
91 Expand csh(1) style brace expressions of the form {a,b}. Brace
92 expressions can be nested. Thus, for example, specifying the
93 pattern "{foo/{,cat,dog},bar}" would return the same results as
94 four separate glob() calls using the strings: "foo/", "foo/cat",
95 "foo/dog", and "bar".
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97 GLOB_NOMAGIC
98 If the pattern contains no metacharacters, then it should be re‐
99 turned as the sole matching word, even if there is no file with
100 that name.
101
102 GLOB_TILDE
103 Carry out tilde expansion. If a tilde ('~') is the only charac‐
104 ter in the pattern, or an initial tilde is followed immediately
105 by a slash ('/'), then the home directory of the caller is sub‐
106 stituted for the tilde. If an initial tilde is followed by a
107 username (e.g., "~andrea/bin"), then the tilde and username are
108 substituted by the home directory of that user. If the username
109 is invalid, or the home directory cannot be determined, then no
110 substitution is performed.
111
112 GLOB_TILDE_CHECK
113 This provides behavior similar to that of GLOB_TILDE. The dif‐
114 ference is that if the username is invalid, or the home direc‐
115 tory cannot be determined, then instead of using the pattern it‐
116 self as the name, glob() returns GLOB_NOMATCH to indicate an er‐
117 ror.
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119 GLOB_ONLYDIR
120 This is a hint to glob() that the caller is interested only in
121 directories that match the pattern. If the implementation can
122 easily determine file-type information, then nondirectory files
123 are not returned to the caller. However, the caller must still
124 check that returned files are directories. (The purpose of this
125 flag is merely to optimize performance when the caller is inter‐
126 ested only in directories.)
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128 If errfunc is not NULL, it will be called in case of an error with the
129 arguments epath, a pointer to the path which failed, and eerrno, the
130 value of errno as returned from one of the calls to opendir(3), read‐
131 dir(3), or stat(2). If errfunc returns nonzero, or if GLOB_ERR is set,
132 glob() will terminate after the call to errfunc.
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134 Upon successful return, pglob->gl_pathc contains the number of matched
135 pathnames and pglob->gl_pathv contains a pointer to the list of point‐
136 ers to matched pathnames. The list of pointers is terminated by a null
137 pointer.
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139 It is possible to call glob() several times. In that case, the
140 GLOB_APPEND flag has to be set in flags on the second and later invoca‐
141 tions.
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143 As a GNU extension, pglob->gl_flags is set to the flags specified, ored
144 with GLOB_MAGCHAR if any metacharacters were found.
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147 On successful completion, glob() returns zero. Other possible returns
148 are:
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150 GLOB_NOSPACE
151 for running out of memory,
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153 GLOB_ABORTED
154 for a read error, and
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156 GLOB_NOMATCH
157 for no found matches.
158
160 For an explanation of the terms used in this section, see at‐
161 tributes(7).
162
163 ┌───────────┬───────────────┬──────────────────────────────────────────┐
164 │Interface │ Attribute │ Value │
165 ├───────────┼───────────────┼──────────────────────────────────────────┤
166 │glob() │ Thread safety │ MT-Unsafe race:utent env sig:ALRM timer │
167 │ │ │ locale │
168 ├───────────┼───────────────┼──────────────────────────────────────────┤
169 │globfree() │ Thread safety │ MT-Safe │
170 └───────────┴───────────────┴──────────────────────────────────────────┘
171 In the above table, utent in race:utent signifies that if any of the
172 functions setutent(3), getutent(3), or endutent(3) are used in parallel
173 in different threads of a program, then data races could occur. glob()
174 calls those functions, so we use race:utent to remind users.
175
177 POSIX.1-2008.
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180 POSIX.1-2001, POSIX.2.
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183 The structure elements gl_pathc and gl_offs are declared as size_t in
184 glibc 2.1, as they should be according to POSIX.2, but are declared as
185 int in glibc 2.0.
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188 The glob() function may fail due to failure of underlying function
189 calls, such as malloc(3) or opendir(3). These will store their error
190 code in errno.
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193 One example of use is the following code, which simulates typing
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195 ls -l *.c ../*.c
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197 in the shell:
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199 glob_t globbuf;
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201 globbuf.gl_offs = 2;
202 glob("*.c", GLOB_DOOFFS, NULL, &globbuf);
203 glob("../*.c", GLOB_DOOFFS | GLOB_APPEND, NULL, &globbuf);
204 globbuf.gl_pathv[0] = "ls";
205 globbuf.gl_pathv[1] = "-l";
206 execvp("ls", &globbuf.gl_pathv[0]);
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209 ls(1), sh(1), stat(2), exec(3), fnmatch(3), malloc(3), opendir(3),
210 readdir(3), wordexp(3), glob(7)
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214Linux man-pages 6.04 2023-03-30 glob(3)