projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| f6ce5b77 WJ |
1 | /*- |
| 2 | * Copyright (c) 1990 The Regents of the University of California. | |
| 3 | * 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. All advertising materials mentioning features or use of this software | |
| 14 | * must display the following acknowledgement: | |
| 15 | * This product includes software developed by the University of | |
| 16 | * California, Berkeley and its contributors. | |
| 17 | * 4. Neither the name of the University nor the names of its contributors | |
| 18 | * may be used to endorse or promote products derived from this software | |
| 19 | * without specific prior written permission. | |
| 20 | * | |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
| 31 | * SUCH DAMAGE. | |
| 32 | */ | |
| 33 | ||
| 34 | #ifndef lint | |
| 35 | static char sccsid[] = "@(#)instr.c 5.2 (Berkeley) 2/28/91"; | |
| 36 | #endif /* not lint */ | |
| 37 | ||
| 38 | #include <sys/types.h> | |
| 39 | #include <sys/wait.h> | |
| 40 | #include <sys/errno.h> | |
| 41 | #include <sys/stat.h> | |
| 42 | #include <unistd.h> | |
| 43 | #include <stdio.h> | |
| 44 | #include <stdlib.h> | |
| 45 | #include <string.h> | |
| 46 | #include "pathnames.h" | |
| 47 | ||
| 48 | instructions() | |
| 49 | { | |
| 50 | extern int errno; | |
| 51 | struct stat sb; | |
| 52 | union wait pstat; | |
| 53 | pid_t pid; | |
| 54 | char *pager, *path; | |
| 55 | ||
| 56 | if (stat(_PATH_INSTR, &sb)) { | |
| 57 | (void)fprintf(stderr, "cribbage: %s: %s.\n", _PATH_INSTR, | |
| 58 | strerror(errno)); | |
| 59 | exit(1); | |
| 60 | } | |
| 61 | switch(pid = vfork()) { | |
| 62 | case -1: | |
| 63 | (void)fprintf(stderr, "cribbage: %s.\n", strerror(errno)); | |
| 64 | exit(1); | |
| 65 | case 0: | |
| 66 | if (!(path = getenv("PAGER"))) | |
| 67 | path = _PATH_MORE; | |
| 68 | if (pager = rindex(path, '/')) | |
| 69 | ++pager; | |
| 70 | pager = path; | |
| 71 | execlp(path, pager, _PATH_INSTR, (char *)NULL); | |
| 72 | (void)fprintf(stderr, "cribbage: %s.\n", strerror(errno)); | |
| 73 | _exit(1); | |
| 74 | default: | |
| 75 | do { | |
| 76 | pid = waitpid(pid, (int *)&pstat, 0); | |
| 77 | } while (pid == -1 && errno == EINTR); | |
| 78 | if (pid == -1 || pstat.w_status) | |
| 79 | exit(1); | |
| 80 | } | |
| 81 | } |