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

NAME
       asprintf, vasprintf - print to allocated string

SYNOPSIS
       #define GNUSOURCE         /* See featuretestmacros(7) */
       #include 

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

       int vasprintf(char **strp, const char *fmt, valist 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 3.53 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/.



GNU                               2013-06-21                       ASPRINTF(3)