util.c revision 1556
11556Srgrimes/*- 21556Srgrimes * Copyright (c) 1991, 1993, 1994 31556Srgrimes * The Regents of the University of California. All rights reserved. 41556Srgrimes * 51556Srgrimes * Redistribution and use in source and binary forms, with or without 61556Srgrimes * modification, are permitted provided that the following conditions 71556Srgrimes * are met: 81556Srgrimes * 1. Redistributions of source code must retain the above copyright 91556Srgrimes * notice, this list of conditions and the following disclaimer. 101556Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111556Srgrimes * notice, this list of conditions and the following disclaimer in the 121556Srgrimes * documentation and/or other materials provided with the distribution. 131556Srgrimes * 3. All advertising materials mentioning features or use of this software 141556Srgrimes * must display the following acknowledgement: 151556Srgrimes * This product includes software developed by the University of 161556Srgrimes * California, Berkeley and its contributors. 171556Srgrimes * 4. Neither the name of the University nor the names of its contributors 181556Srgrimes * may be used to endorse or promote products derived from this software 191556Srgrimes * without specific prior written permission. 201556Srgrimes * 211556Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221556Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231556Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241556Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251556Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261556Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271556Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281556Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291556Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301556Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311556Srgrimes * SUCH DAMAGE. 321556Srgrimes */ 331556Srgrimes 341556Srgrimes#ifndef lint 351556Srgrimesstatic char sccsid[] = "@(#)util.c 8.3 (Berkeley) 4/2/94"; 361556Srgrimes#endif /* not lint */ 371556Srgrimes 381556Srgrimes#include <sys/types.h> 391556Srgrimes#include <sys/stat.h> 401556Srgrimes 411556Srgrimes#include <err.h> 421556Srgrimes#include <stdio.h> 431556Srgrimes#include <stdlib.h> 441556Srgrimes#include <unistd.h> 451556Srgrimes 461556Srgrimes#include "stty.h" 471556Srgrimes#include "extern.h" 481556Srgrimes 491556Srgrimes/* 501556Srgrimes * Gross, but since we're changing the control descriptor from 1 to 0, most 511556Srgrimes * users will be probably be doing "stty > /dev/sometty" by accident. If 1 521556Srgrimes * and 2 are both ttys, but not the same, assume that 1 was incorrectly 531556Srgrimes * redirected. 541556Srgrimes */ 551556Srgrimesvoid 561556Srgrimescheckredirect() 571556Srgrimes{ 581556Srgrimes struct stat sb1, sb2; 591556Srgrimes 601556Srgrimes if (isatty(STDOUT_FILENO) && isatty(STDERR_FILENO) && 611556Srgrimes !fstat(STDOUT_FILENO, &sb1) && !fstat(STDERR_FILENO, &sb2) && 621556Srgrimes (sb1.st_rdev != sb2.st_rdev)) 631556Srgrimeswarn("stdout appears redirected, but stdin is the control descriptor"); 641556Srgrimes} 65