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 #if 0 35 #ifndef lint 36 static const char copyright[] = 37 "@(#) Copyright (c) 1989, 1993\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39 #endif /* not lint */ 40 41 #ifndef lint 42 static char sccsid[] = "@(#)nohup.c 8.1 (Berkeley) 6/6/93"; 43 #endif /* not lint */ 44 #endif 45 #include <sys/cdefs.h> 46 __FBSDID("$FreeBSD$"); 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 <unistd.h> 58 59 static void dofile(void); 60 static void usage(void); 61 62 #define FILENAME "nohup.out" 63 /* 64 * POSIX mandates that we exit with: 65 * 126 - If the utility was found, but failed to execute. 66 * 127 - If any other error occurred. 67 */ 68 #define EXIT_NOEXEC 126 69 #define EXIT_NOTFOUND 127 70 #define EXIT_MISC 127 71 72 int 73 main(int argc, char *argv[]) 74 { 75 int exit_status; 76 77 while (getopt(argc, argv, "") != -1) 78 usage(); 79 argc -= optind; 80 argv += optind; 81 if (argc < 1) 82 usage(); 83 84 if (isatty(STDOUT_FILENO)) 85 dofile(); 86 if (isatty(STDERR_FILENO) && dup2(STDOUT_FILENO, STDERR_FILENO) == -1) 87 /* may have just closed stderr */ 88 err(EXIT_MISC, "%s", argv[0]); 89 90 (void)signal(SIGHUP, SIG_IGN); 91 92 execvp(*argv, argv); 93 exit_status = (errno == ENOENT) ? EXIT_NOTFOUND : EXIT_NOEXEC; 94 err(exit_status, "%s", argv[0]); 95 } 96 97 static void 98 dofile(void) 99 { 100 int fd; 101 char path[MAXPATHLEN]; 102 const char *p; 103 104 /* 105 * POSIX mandates if the standard output is a terminal, the standard 106 * output is appended to nohup.out in the working directory. Failing 107 * that, it will be appended to nohup.out in the directory obtained 108 * from the HOME environment variable. If file creation is required, 109 * the mode_t is set to S_IRUSR | S_IWUSR. 110 */ 111 p = FILENAME; 112 fd = open(p, O_RDWR | O_CREAT | O_APPEND, S_IRUSR | S_IWUSR); 113 if (fd != -1) 114 goto dupit; 115 if ((p = getenv("HOME")) != NULL && *p != '\0' && 116 (size_t)snprintf(path, sizeof(path), "%s/%s", p, FILENAME) < 117 sizeof(path)) { 118 fd = open(p = path, O_RDWR | O_CREAT | O_APPEND, 119 S_IRUSR | S_IWUSR); 120 if (fd != -1) 121 goto dupit; 122 } 123 errx(EXIT_MISC, "can't open a nohup.out file"); 124 125 dupit: 126 if (dup2(fd, STDOUT_FILENO) == -1) 127 err(EXIT_MISC, NULL); 128 (void)fprintf(stderr, "appending output to %s\n", p); 129 } 130 131 static void 132 usage(void) 133 { 134 (void)fprintf(stderr, "usage: nohup [--] utility [arguments]\n"); 135 exit(EXIT_MISC); 136 } 137