/* $OpenBSD: nohup.c,v 1.14 2009/10/27 23:59:41 deraadt Exp $ */ /* $NetBSD: nohup.c,v 1.6 1995/08/31 23:35:25 jtc Exp $ */ /* * Copyright (c) 1989 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/param.h> #include <sys/file.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <err.h> static void dofile(void); __dead static void usage(void); /* * nohup shall exit with one of the following values: * 126 - The utility was found but could not be invoked. * 127 - An error occurred in the nohup utility, or the utility could * not be found. */ #define EXIT_NOEXEC 126 #define EXIT_NOTFOUND 127 #define EXIT_MISC 127 /* * If the standard output is a terminal, all output written to * its standard output shall be appended to the end of the file * nohup.out in the current directory. If nohup.out cannot be * created or opened for appending, the output shall be appended * to the end of the file nohup.out in the directory specified * by the HOME environment variable. * * If a file is created, the file's permission bits shall be * set to S_IRUSR | S_IWUSR. */ #define FILENAME "nohup.out" int main(int argc, char *argv[]) { int exit_status; if (argc < 2) usage(); if (isatty(STDOUT_FILENO)) dofile(); if (isatty(STDERR_FILENO) && dup2(STDOUT_FILENO, STDERR_FILENO) == -1) { /* may have just closed stderr */ (void)fprintf(stdin, "nohup: %s\n", strerror(errno)); exit(EXIT_MISC); } /* * The nohup utility shall take the standard action for all signals * except that SIGHUP shall be ignored. */ (void)signal(SIGHUP, SIG_IGN); execvp(argv[1], &argv[1]); exit_status = (errno == ENOENT) ? EXIT_NOTFOUND : EXIT_NOEXEC; err(exit_status, "%s", argv[1]); } static void dofile(void) { int fd; const char *p; char path[MAXPATHLEN]; p = FILENAME; if ((fd = open(p, O_RDWR|O_CREAT|O_APPEND, S_IRUSR|S_IWUSR)) >= 0) goto dupit; if ((p = getenv("HOME")) != NULL && *p != '\0' && (strlen(p) + strlen(FILENAME) + 1) < sizeof(path)) { (void)strlcpy(path, p, sizeof(path)); (void)strlcat(path, "/", sizeof(path)); (void)strlcat(path, FILENAME, sizeof(path)); if ((fd = open(p = path, O_RDWR|O_CREAT|O_APPEND, S_IRUSR|S_IWUSR)) >= 0) goto dupit; } errx(EXIT_MISC, "can't open a nohup.out file"); dupit: (void)lseek(fd, (off_t)0, SEEK_END); if (dup2(fd, STDOUT_FILENO) == -1) err(EXIT_MISC, NULL); (void)fprintf(stderr, "sending output to %s\n", p); } __dead static void usage(void) { (void)fprintf(stderr, "usage: nohup utility [arg ...]\n"); exit(EXIT_MISC); }