1 /* $NetBSD: instr.c,v 1.9 1999/11/09 15:06:32 drochner Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)instr.c 8.1 (Berkeley) 5/31/93"; 40 #else 41 __RCSID("$NetBSD: instr.c,v 1.9 1999/11/09 15:06:32 drochner Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <sys/wait.h> 47 #include <sys/stat.h> 48 49 #include <curses.h> 50 #include <err.h> 51 #include <fcntl.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <unistd.h> 56 #include <errno.h> 57 58 #include "deck.h" 59 #include "cribbage.h" 60 #include "pathnames.h" 61 62 void 63 instructions() 64 { 65 int pstat; 66 int fd; 67 pid_t pid; 68 const char *path; 69 70 switch (pid = vfork()) { 71 case -1: 72 err(1, "vfork"); 73 case 0: 74 /* Follow the same behaviour for pagers as defined in POSIX.2 75 * for mailx and man. We only use a pager if stdout is 76 * a terminal, and we pass the file on stdin to sh -c pager. 77 */ 78 if (!isatty(1)) 79 path = "cat"; 80 else { 81 if (!(path = getenv("PAGER")) || (*path == 0)) 82 path = _PATH_MORE; 83 } 84 if ((fd = open(_PATH_INSTR, O_RDONLY)) == -1) { 85 warn("open %s", _PATH_INSTR); 86 _exit(1); 87 } 88 if (dup2(fd, 0) == -1) { 89 warn("dup2"); 90 _exit(1); 91 } 92 execl("/bin/sh", "sh", "-c", path, NULL); 93 warn(NULL); 94 _exit(1); 95 default: 96 do { 97 pid = waitpid(pid, &pstat, 0); 98 } while (pid == -1 && errno == EINTR); 99 if (pid == -1 || WEXITSTATUS(pstat)) 100 exit(1); 101 } 102 } 103