1ARGZ_ADD(3) Linux Programmer's Manual ARGZ_ADD(3)
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6 argz_add, argz_add_sep, argz_append, argz_count, argz_create, argz_cre‐
7 ate_sep, argz_delete, argz_extract, argz_insert, argz_next, argz_re‐
8 place, argz_stringify - functions to handle an argz list
9
11 #include <argz.h>
12 error_t argz_add(char **restrict argz, size_t *restrict argz_len,
14 const char *restrict str);
15 error_t argz_add_sep(char **restrict argz, size_t *restrict argz_len,
17 const char *restrict str, int delim);
18 error_t argz_append(char **restrict argz, size_t *restrict argz_len,
20 const char *restrict buf, size_t buf_len);
21 size_t argz_count(const char *argz, size_t argz_len);
23 error_t argz_create(char *const argv[], char **restrict argz,
25 size_t *restrict argz_len);
26 error_t argz_create_sep(const char *restrict str, int sep,
28 char **restrict argz, size_t *restrict argz_len);
29 void argz_delete(char **restrict argz, size_t *restrict argz_len,
31 char *restrict entry);
32 void argz_extract(const char *restrict argz, size_t argz_len,
34 char **restrict argv);
35 error_t argz_insert(char **restrict argz, size_t *restrict argz_len,
37 char *restrict before, const char *restrict entry);
38 char *argz_next(const char *restrict argz, size_t argz_len,
40 const char *restrict entry);
41 error_t argz_replace(char **restrict argz, size_t *restrict argz_len,
43 const char *restrict str, const char *restrict with,
44 unsigned int *restrict replace_count);
45 void argz_stringify(char *argz, size_t len, int sep);
47
49 These functions are glibc-specific.
50 An argz vector is a pointer to a character buffer together with a
52 length. The intended interpretation of the character buffer is an ar‐
53 ray of strings, where the strings are separated by null bytes ('\0').
54 If the length is nonzero, the last byte of the buffer must be a null
55 byte.
56 These functions are for handling argz vectors. The pair (NULL,0) is an
58 argz vector, and, conversely, argz vectors of length 0 must have null
59 pointer. Allocation of nonempty argz vectors is done using malloc(3),
60 so that free(3) can be used to dispose of them again.
61 argz_add() adds the string str at the end of the array *argz, and up‐
63 dates *argz and *argz_len.
64 argz_add_sep() is similar, but splits the string str into substrings
66 separated by the delimiter delim. For example, one might use this on a
67 UNIX search path with delimiter ':'.
68 argz_append() appends the argz vector (buf, buf_len) after
70 (*argz, *argz_len) and updates *argz and *argz_len. (Thus, *argz_len
71 will be increased by buf_len.)
72 argz_count() counts the number of strings, that is, the number of null
74 bytes ('\0'), in (argz, argz_len).
75 argz_create() converts a UNIX-style argument vector argv, terminated by
77 (char *) 0, into an argz vector (*argz, *argz_len).
78 argz_create_sep() converts the null-terminated string str into an argz
80 vector (*argz, *argz_len) by breaking it up at every occurrence of the
81 separator sep.
82 argz_delete() removes the substring pointed to by entry from the argz
84 vector (*argz, *argz_len) and updates *argz and *argz_len.
85 argz_extract() is the opposite of argz_create(). It takes the argz
87 vector (argz, argz_len) and fills the array starting at argv with
88 pointers to the substrings, and a final NULL, making a UNIX-style argv
89 vector. The array argv must have room for argz_count(argz, argz_len) +
90 1 pointers.
91 argz_insert() is the opposite of argz_delete(). It inserts the argu‐
93 ment entry at position before into the argz vector (*argz, *argz_len)
94 and updates *argz and *argz_len. If before is NULL, then entry will
95 inserted at the end.
96 argz_next() is a function to step through the argz vector. If entry is
98 NULL, the first entry is returned. Otherwise, the entry following is
99 returned. It returns NULL if there is no following entry.
100 argz_replace() replaces each occurrence of str with with, reallocating
102 argz as necessary. If replace_count is non-NULL, *replace_count will
103 be incremented by the number of replacements.
104 argz_stringify() is the opposite of argz_create_sep(). It transforms
106 the argz vector into a normal string by replacing all null bytes ('\0')
107 except the last by sep.
108
110 All argz functions that do memory allocation have a return type of er‐
111 ror_t (an integer type), and return 0 for success, and ENOMEM if an al‐
112 location error occurs.
113
115 For an explanation of the terms used in this section, see at‐
116 tributes(7).
117 ┌────────────────────────────────────────────┬───────────────┬─────────┐
119 │Interface │ Attribute │ Value │
120 ├────────────────────────────────────────────┼───────────────┼─────────┤
121 │argz_add(), argz_add_sep(), argz_append(), │ Thread safety │ MT-Safe │
122 │argz_count(), argz_create(), │ │ │
123 │argz_create_sep(), argz_delete(), │ │ │
124 │argz_extract(), argz_insert(), argz_next(), │ │ │
125 │argz_replace(), argz_stringify() │ │ │
126 └────────────────────────────────────────────┴───────────────┴─────────┘
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129 These functions are a GNU extension.
130
132 Argz vectors without a terminating null byte may lead to Segmentation
133 Faults.
134
136 envz_add(3)
137
139 This page is part of release 5.13 of the Linux man-pages project. A
140 description of the project, information about reporting bugs, and the
141 latest version of this page, can be found at
142 https://www.kernel.org/doc/man-pages/.
143 2021-03-22 ARGZ_ADD(3)