xref: /titanic_44/usr/src/lib/libast/common/stdio/ungetwc.c (revision 8b0ef7ed9d02af20a3d5106d84a4fc6aa0d7dd9f)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #pragma prototyped
23 
24 #include "stdhdr.h"
25 
26 wint_t
27 ungetwc(wint_t c, Sfio_t* f)
28 {
29 	register unsigned char*	s = (unsigned char*)&c;
30 	register unsigned char*	e = s + sizeof(c);
31 
32 	STDIO_INT(f, "ungetwc", wint_t, (wint_t, Sfio_t*), (c, f))
33 
34 	FWIDE(f, WEOF);
35 	while (s < e)
36 		if (sfungetc(f, *s++) == EOF)
37 			return WEOF;
38 	return c;
39 }
40