daemon.c 3.4 KB

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  1. /* vi: set sw=4 ts=4: */
  2. /* daemon implementation for uClibc
  3. *
  4. * Copyright (c) 1991, 1993
  5. * The Regents of the University of California. All rights reserved.
  6. *
  7. * Modified for uClibc by Erik Andersen <andersee@debian.org>
  8. *
  9. * This program is free software; you can redistribute it and/or modify it
  10. * under the terms of the GNU Library General Public License as published by
  11. * the Free Software Foundation; either version 2 of the License, or (at your
  12. * option) any later version.
  13. *
  14. * This program is distributed in the hope that it will be useful, but WITHOUT
  15. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
  17. * for more details.
  18. *
  19. * You should have received a copy of the GNU Library General Public License
  20. * along with this program; if not, write to the Free Software Foundation,
  21. * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22. *
  23. * Original copyright notice is retained at the end of this file.
  24. */
  25. #include <stdio.h>
  26. #include <features.h>
  27. #include <fcntl.h>
  28. #include <paths.h>
  29. #include <unistd.h>
  30. /* Note that this file should not be compiled in
  31. * unless __ARCH_HAS_MMU__ is defined */
  32. int daemon( int nochdir, int noclose )
  33. {
  34. int fd;
  35. switch (fork()) {
  36. case -1:
  37. return(-1);
  38. case 0:
  39. break;
  40. default:
  41. _exit(0);
  42. }
  43. if (setsid() == -1)
  44. return(-1);
  45. /* Make certain we are not a session leader, or else we
  46. * might reacquire a controlling terminal */
  47. if (fork())
  48. _exit(0);
  49. if (!nochdir)
  50. chdir("/");
  51. if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
  52. dup2(fd, STDIN_FILENO);
  53. dup2(fd, STDOUT_FILENO);
  54. dup2(fd, STDERR_FILENO);
  55. if (fd > 2)
  56. close(fd);
  57. }
  58. return(0);
  59. }
  60. /*-
  61. * Copyright (c) 1990, 1993
  62. * The Regents of the University of California. All rights reserved.
  63. *
  64. * Redistribution and use in source and binary forms, with or without
  65. * modification, are permitted provided that the following conditions
  66. * are met:
  67. * 1. Redistributions of source code must retain the above copyright
  68. * notice, this list of conditions and the following disclaimer.
  69. * 2. Redistributions in binary form must reproduce the above copyright
  70. * notice, this list of conditions and the following disclaimer in the
  71. * documentation and/or other materials provided with the distribution.
  72. *
  73. * 3. <BSD Advertising Clause omitted per the July 22, 1999 licensing change
  74. * ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change>
  75. *
  76. * 4. Neither the name of the University nor the names of its contributors
  77. * may be used to endorse or promote products derived from this software
  78. * without specific prior written permission.
  79. *
  80. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  81. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  82. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  83. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  84. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  85. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  86. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  87. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  88. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  89. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  90. * SUCH DAMAGE.
  91. */