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 * 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 #if 0 31 #ifndef lint 32 static const char copyright[] = 33 "@(#) Copyright (c) 1989, 1993\n\ 34 The Regents of the University of California. All rights reserved.\n"; 35 #endif /* not lint */ 36 37 #ifndef lint 38 static char sccsid[] = "@(#)nohup.c 8.1 (Berkeley) 6/6/93"; 39 #endif /* not lint */ 40 #endif 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include <sys/param.h> 45 #include <sys/stat.h> 46 47 #include <err.h> 48 #include <errno.h> 49 #include <fcntl.h> 50 #include <signal.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 static void dofile(void); 57 static void usage(void); 58 59 #define FILENAME "nohup.out" 60 /* 61 * POSIX mandates that we exit with: 62 * 126 - If the utility was found, but failed to execute. 63 * 127 - If any other error occurred. 64 */ 65 #define EXIT_NOEXEC 126 66 #define EXIT_NOTFOUND 127 67 #define EXIT_MISC 127 68 69 int 70 main(int argc, char *argv[]) 71 { 72 int exit_status; 73 74 while (getopt(argc, argv, "") != -1) 75 usage(); 76 argc -= optind; 77 argv += optind; 78 if (argc < 1) 79 usage(); 80 81 if (isatty(STDOUT_FILENO)) 82 dofile(); 83 if (isatty(STDERR_FILENO) && dup2(STDOUT_FILENO, STDERR_FILENO) == -1) 84 /* may have just closed stderr */ 85 err(EXIT_MISC, "%s", argv[0]); 86 87 (void)signal(SIGHUP, SIG_IGN); 88 89 execvp(*argv, argv); 90 exit_status = (errno == ENOENT) ? EXIT_NOTFOUND : EXIT_NOEXEC; 91 err(exit_status, "%s", argv[0]); 92 } 93 94 static void 95 dofile(void) 96 { 97 int fd; 98 char path[MAXPATHLEN]; 99 const char *p; 100 101 /* 102 * POSIX mandates if the standard output is a terminal, the standard 103 * output is appended to nohup.out in the working directory. Failing 104 * that, it will be appended to nohup.out in the directory obtained 105 * from the HOME environment variable. If file creation is required, 106 * the mode_t is set to S_IRUSR | S_IWUSR. 107 */ 108 p = FILENAME; 109 fd = open(p, O_RDWR | O_CREAT | O_APPEND, S_IRUSR | S_IWUSR); 110 if (fd != -1) 111 goto dupit; 112 if ((p = getenv("HOME")) != NULL && *p != '\0' && 113 (size_t)snprintf(path, sizeof(path), "%s/%s", p, FILENAME) < 114 sizeof(path)) { 115 fd = open(p = path, O_RDWR | O_CREAT | O_APPEND, 116 S_IRUSR | S_IWUSR); 117 if (fd != -1) 118 goto dupit; 119 } 120 errx(EXIT_MISC, "can't open a nohup.out file"); 121 122 dupit: 123 if (dup2(fd, STDOUT_FILENO) == -1) 124 err(EXIT_MISC, NULL); 125 (void)fprintf(stderr, "appending output to %s\n", p); 126 } 127 128 static void 129 usage(void) 130 { 131 (void)fprintf(stderr, "usage: nohup [--] utility [arguments]\n"); 132 exit(EXIT_MISC); 133 } 134