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 * 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 const char copyright[] = 36 "@(#) Copyright (c) 1989, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)nohup.c 8.1 (Berkeley) 6/6/93"; 43 #endif 44 static const char rcsid[] = 45 "$FreeBSD$"; 46 #endif /* not lint */ 47 48 #include <sys/param.h> 49 #include <sys/stat.h> 50 51 #include <err.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <signal.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 60 static void dofile __P((void)); 61 static void usage __P((void)); 62 63 #define FILENAME "nohup.out" 64 /* 65 * POSIX mandates that we exit with: 66 * 126 - If the utility was found, but failed to execute. 67 * 127 - If any other error occurred. 68 */ 69 #define EXIT_NOEXEC 126 70 #define EXIT_NOTFOUND 127 71 #define EXIT_MISC 127 72 73 int 74 main(argc, argv) 75 int argc; 76 char *argv[]; 77 { 78 int exit_status; 79 80 while (getopt(argc, argv, "") != -1) 81 usage(); 82 argc -= optind; 83 argv += optind; 84 if (argc < 1) 85 usage(); 86 87 if (isatty(STDOUT_FILENO)) 88 dofile(); 89 if (isatty(STDERR_FILENO) && dup2(STDOUT_FILENO, STDERR_FILENO) == -1) 90 /* may have just closed stderr */ 91 err(EXIT_MISC, "%s", argv[0]); 92 93 (void)signal(SIGHUP, SIG_IGN); 94 95 execvp(*argv, argv); 96 exit_status = (errno == ENOENT) ? EXIT_NOTFOUND : EXIT_NOEXEC; 97 err(exit_status, "%s", argv[0]); 98 } 99 100 static void 101 dofile() 102 { 103 int fd; 104 char path[MAXPATHLEN]; 105 const char *p; 106 107 /* 108 * POSIX mandates if the standard output is a terminal, the standard 109 * output is appended to nohup.out in the working directory. Failing 110 * that, it will be appended to nohup.out in the directory obtained 111 * from the HOME environment variable. If file creation is required, 112 * the mode_t is set to S_IRUSR | S_IWUSR. 113 */ 114 p = FILENAME; 115 fd = open(p, O_RDWR | O_CREAT | O_APPEND, S_IRUSR | S_IWUSR); 116 if (fd != -1) 117 goto dupit; 118 if ((p = getenv("HOME")) != NULL && *p != '\0' && 119 (size_t)snprintf(path, sizeof(path), "%s/%s", p, FILENAME) < 120 sizeof(path)) { 121 fd = open(p = path, O_RDWR | O_CREAT | O_APPEND, 122 S_IRUSR | S_IWUSR); 123 if (fd != -1) 124 goto dupit; 125 } 126 errx(EXIT_MISC, "can't open a nohup.out file"); 127 128 dupit: 129 if (dup2(fd, STDOUT_FILENO) == -1) 130 err(EXIT_MISC, NULL); 131 (void)fprintf(stderr, "appending output to %s\n", p); 132 } 133 134 static void 135 usage() 136 { 137 (void)fprintf(stderr, "usage: nohup [--] command [arguments]\n"); 138 exit(EXIT_MISC); 139 } 140