xref: /netbsd/lib/libc/termios/tcflush.c (revision 90275da6)
1 /*	$NetBSD: tcflush.c,v 1.10 2012/06/25 22:32:46 abs Exp $	*/
2 
3 /*-
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)termios.c	8.2 (Berkeley) 2/21/94";
36 #else
37 __RCSID("$NetBSD: tcflush.c,v 1.10 2012/06/25 22:32:46 abs Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include "namespace.h"
42 #include <sys/ioctl.h>
43 
44 #include <assert.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <termios.h>
48 
49 #ifdef __weak_alias
__weak_alias(tcflush,_tcflush)50 __weak_alias(tcflush,_tcflush)
51 #endif
52 
53 int
54 tcflush(int fd, int which)
55 {
56 	int com;
57 
58 	_DIAGASSERT(fd != -1);
59 
60 	switch (which) {
61 	case TCIFLUSH:
62 		com = FREAD;
63 		break;
64 	case TCOFLUSH:
65 		com = FWRITE;
66 		break;
67 	case TCIOFLUSH:
68 		com = FREAD | FWRITE;
69 		break;
70 	default:
71 		errno = EINVAL;
72 		return (-1);
73 	}
74 	return (ioctl(fd, TIOCFLUSH, &com));
75 }
76