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NAME

       asprintf, vasprintf - print to allocated string

SYNOPSIS

       #define _GNU_SOURCE
       #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, 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), feature_test_macros(7)

COLOPHON

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