1 /*- 2 * Copyright (c) 1991, 1993, 1994 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 * 4. 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 #ifndef lint 31 #if 0 32 static char sccsid[] = "@(#)util.c 8.3 (Berkeley) 4/2/94"; 33 #endif 34 #endif /* not lint */ 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include <sys/types.h> 39 #include <sys/stat.h> 40 41 #include <err.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <unistd.h> 45 46 #include "stty.h" 47 #include "extern.h" 48 49 /* 50 * Gross, but since we're changing the control descriptor from 1 to 0, most 51 * users will be probably be doing "stty > /dev/sometty" by accident. If 1 52 * and 2 are both ttys, but not the same, assume that 1 was incorrectly 53 * redirected. 54 */ 55 void 56 checkredirect(void) 57 { 58 struct stat sb1, sb2; 59 60 if (isatty(STDOUT_FILENO) && isatty(STDERR_FILENO) && 61 !fstat(STDOUT_FILENO, &sb1) && !fstat(STDERR_FILENO, &sb2) && 62 (sb1.st_rdev != sb2.st_rdev)) 63 warnx("stdout appears redirected, but stdin is the control descriptor"); 64 } 65