glibc/stdio/vsprintf.c

51 lines
1.5 KiB
C

/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <ansidecl.h>
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
/* Write formatted output to S according to the format string
FORMAT, using the argument list in ARG. */
int
DEFUN(vsprintf, (s, format, arg),
char *s AND CONST char *format AND va_list arg)
{
int done;
FILE f;
memset((PTR) &f, 0, sizeof(f));
f.__magic = _IOMAGIC;
f.__mode.__write = 1;
f.__bufp = f.__buffer = (char *) s;
f.__put_limit = (char *) ULONG_MAX;
f.__bufsize = (size_t) (f.__put_limit - f.__bufp);
f.__get_limit = f.__buffer;
f.__room_funcs.__output = NULL;
f.__seen = 1;
done = vfprintf(&f, format, arg);
*f.__bufp = '\0';
return done;
}