1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #if defined(LIBC_SCCS) && !defined(lint) 31 static char rcsid[] = "$OpenBSD: tcflow.c,v 1.4 2003/06/11 21:03:09 deraadt Exp $"; 32 #endif /* LIBC_SCCS and not lint */ 33 34 #include <sys/ioctl.h> 35 #include <termios.h> 36 #include <unistd.h> 37 #include <errno.h> 38 39 int 40 tcflow(int fd, int action) 41 { 42 struct termios term; 43 u_char c; 44 45 switch (action) { 46 case TCOOFF: 47 return (ioctl(fd, TIOCSTOP, 0)); 48 case TCOON: 49 return (ioctl(fd, TIOCSTART, 0)); 50 case TCION: 51 case TCIOFF: 52 if (tcgetattr(fd, &term) == -1) 53 return (-1); 54 c = term.c_cc[action == TCIOFF ? VSTOP : VSTART]; 55 if (c != _POSIX_VDISABLE && write(fd, &c, sizeof(c)) == -1) 56 return (-1); 57 return (0); 58 default: 59 errno = EINVAL; 60 return (-1); 61 } 62 /* NOTREACHED */ 63 } 64