argz_add
ARGZ_ADD(3) ARGZ_ADD(3)
NAME
argz_add, argz_add_sep, argz_append, argz_count, argz_create, argz_cre-
ate_sep, argz_delete, argz_extract, argz_insert, argz_next,
argz_replace, argz_stringify - functions to handle an argz list
SYNOPSIS
#include <argz.h>
error_t
argz_add(char **argz, size_t *argz_len, const char *str);
error_t
argz_add_sep(char **argz, size_t *argz_len,
const char *str, int delim);
error_t
argz_append(char **argz, size_t *argz_len,
const char *buf, size_t buf_len);
size_t
argz_count(const char *argz, size_t argz_len);
error_t
argz_create(char * const argv[], char **argz,
size_t *argz_len);
error_t
argz_create_sep(const char *str, int sep, char **argz,
size_t *argz_len);
error_t
argz_delete(char **argz, size_t *argz_len, char *entry);
void
argz_extract(char *argz, size_t argz_len, char **argv);
error_t
argz_insert (char **argz, size_t *argz_len, char *before,
const char *entry);
char *
argz_next(char *argz, size_t argz_len, const char *entry);
error_t
argz_replace(char **argz, size_t *argz_len, const char *str,
const char *with, unsigned int *replace_count);
void
argz_stringify(char *argz, size_t len, int sep);
DESCRIPTION
These functions are glibc-specific.
An argz vector is a pointer to a character buffer together with a
length. The intended interpretation of the character buffer is array
of strings, where the strings are separated by NUL bytes. If the
length is nonzero, the last byte of the buffer must be a NUL.
These functions are for handling argz vectors. The pair (NULL,0) is an
argz vector, and, conversely, argz vectors of length 0 must have NULL
pointer. Allocation of nonempty argz vectors is done using malloc(3),
so that free(3) can be used to dispose of them again.
argz_add() adds the string str at the end of the array *argz, and
updates *argz and *argz_len.
argz_add_sep() is similar, but splits the string str into substrings
separated by the delimiter delim. For example, one might use this on a
Unix search path with delimiter ':'.
argz_append() appends the argz vector (buf,buf_len) after
(*argz,*argz_len) and updates *argz and *argz_len. (Thus, *argz_len
will be increased by buf_len.)
argz_count() counts the number of strings, that is, the number of NUL
bytes, in (argz,argz_len).
argz_create() converts a Unix-style argument vector argv, terminated by
(char *) 0, into an argz vector (*argz,*argz_len).
argz_create_sep() converts the NUL-terminated string str into an argz
vector (*argz,*argz_len) by breaking it up at every occurrence of the
separator sep.
argz_delete() removes the substring pointed to by entry from the argz
vector (*argz,*argz_len) and updates *argz and *argz_len.
argz_extract() is the opposite of argz_create(). It takes the argz
vector (argz,argz_len) and fills the array starting at argv with point-
ers to the substrings, and a final NULL, making a Unix-style argv vec-
tor. The array argv must have room for argz_count(argz,argz_len) + 1
pointers.
argz_insert() is the opposite of argz_delete(). It inserts the argu-
ment entry at position before into the argz vector (*argz,*argz_len)
and updates *argz and *argz_len. If before is NULL, then entry will
inserted at the end.
argz_next() is a function to step trough the argz vector. If entry is
NULL, the first entry is returned. Otherwise, the entry following is
returned. It returns NULL if there is no following entry.
argz_replace() replaces each occurrence of str with with, reallocating
argz as necessary. If replace_count is non-NULL, *replace_count will be
incremented by the number of replacements.
argz_stringify() is the opposite of argz_create_sep(). It transforms
the argz vector into a normal string by replacing all NULs except the
last by sep.
RETURN VALUE
All argz functions that do memory allocation have a return type of
error_t, and return 0 for success, and ENOMEM if an allocation error
occurs.
BUGS
Argz vectors without final NUL may lead to Segmentation Faults.
NOTES
These functions are a GNU extension. Handle with care.
SEE ALSO
envz(3)
ARGZ_ADD(3)