ARGZ_ADD(3)                                         Linux Programmer's Manual                                        ARGZ_ADD(3)



NAME
       argz_add,  argz_add_sep,  argz_append,  argz_count, argz_create, argz_create_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 an array of strings, where the strings are separated by null bytes ('\0').  If the length is nonzero, the last
       byte of the buffer must be a null byte.

       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 null bytes ('\0'), 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  null-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 pointers to the substrings, and a final NULL, making a Unix-style argv vector.  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 argument 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 null bytes ('\0') 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.

CONFORMING TO
       These functions are a GNU extension.  Handle with care.

BUGS
       Argz vectors without a terminating null byte may lead to Segmentation Faults.

SEE ALSO
       envz_add(3)

COLOPHON
       This page is part of release 3.25 of the Linux man-pages project.  A description of the project,  and  information  about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



                                                           2007-05-18                                                ARGZ_ADD(3)