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



NAME
       asprintf, vasprintf - print to allocated string

SYNOPSIS
       #define _GNU_SOURCE         /* See feature_test_macros(7) */
       #include <stdio.h>

       int asprintf(char **strp, const char *fmt, ...);

       int vasprintf(char **strp, const char *fmt, va_list ap);

DESCRIPTION
       The functions asprintf() and vasprintf() are analogs of sprintf(3) and vsprintf(3), except
       that they allocate a string large enough to hold the output including the terminating null
       byte  ('\0'),  and  return a pointer to it via the first argument.  This pointer should be
       passed to free(3) to release the allocated storage when it is no longer needed.

RETURN VALUE
       When successful, these functions return the number of bytes printed, just like sprintf(3).
       If  memory  allocation  wasn't  possible, or some other error occurs, these functions will
       return -1, and the contents of strp is undefined.

CONFORMING TO
       These functions are GNU extensions, not in C or POSIX.   They  are  also  available  under
       *BSD.  The FreeBSD implementation sets strp to NULL on error.

SEE ALSO
       free(3), malloc(3), printf(3)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at http://www.kernel.org/doc/man-pages/.



GNU                                         2013-06-21                                ASPRINTF(3)