daemon.c 2.5 KB

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  1. /* OPENBSD ORIGINAL: lib/libc/gen/daemon.c */
  2. /*-
  3. * Copyright (c) 1990, 1993
  4. * The Regents of the University of California. All rights reserved.
  5. *
  6. * Redistribution and use in source and binary forms, with or without
  7. * modification, are permitted provided that the following conditions
  8. * are met:
  9. * 1. Redistributions of source code must retain the above copyright
  10. * notice, this list of conditions and the following disclaimer.
  11. * 2. Redistributions in binary form must reproduce the above copyright
  12. * notice, this list of conditions and the following disclaimer in the
  13. * documentation and/or other materials provided with the distribution.
  14. * 3. Neither the name of the University nor the names of its contributors
  15. * may be used to endorse or promote products derived from this software
  16. * without specific prior written permission.
  17. *
  18. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28. * SUCH DAMAGE.
  29. */
  30. #include "common.h"
  31. #ifndef HAVE_DAEMON
  32. #if defined(LIBC_SCCS) && !defined(lint)
  33. static char rcsid[] = "$OpenBSD: daemon.c,v 1.5 2003/07/15 17:32:41 deraadt Exp $";
  34. #endif /* LIBC_SCCS and not lint */
  35. int
  36. daemon(int nochdir, int noclose)
  37. {
  38. int fd;
  39. switch (fork()) {
  40. case -1:
  41. return (-1);
  42. case 0:
  43. #ifdef HAVE_CYGWIN
  44. register_9x_service();
  45. #endif
  46. break;
  47. default:
  48. #ifdef HAVE_CYGWIN
  49. /*
  50. * This sleep avoids a race condition which kills the
  51. * child process if parent is started by a NT/W2K service.
  52. */
  53. sleep(1);
  54. #endif
  55. _exit(0);
  56. }
  57. if (setsid() == -1)
  58. return (-1);
  59. if (!nochdir)
  60. (void)chdir("/");
  61. if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
  62. (void)dup2(fd, STDIN_FILENO);
  63. (void)dup2(fd, STDOUT_FILENO);
  64. (void)dup2(fd, STDERR_FILENO);
  65. if (fd > 2)
  66. (void)close (fd);
  67. }
  68. return (0);
  69. }
  70. #endif /* !HAVE_DAEMON */