spawn_faction_adddup2.c 1.8 KB

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  1. /* Copyright (C) 2000 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. The GNU C Library is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU Lesser General Public
  5. License as published by the Free Software Foundation; either
  6. version 2.1 of the License, or (at your option) any later version.
  7. The GNU C Library is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10. Lesser General Public License for more details.
  11. You should have received a copy of the GNU Lesser General Public
  12. License along with the GNU C Library; if not, see
  13. <http://www.gnu.org/licenses/>. */
  14. #include <errno.h>
  15. #include <spawn.h>
  16. #include <unistd.h>
  17. #include "spawn_int.h"
  18. /* Add an action to FILE-ACTIONS which tells the implementation to call
  19. `dup2' for the given file descriptors during the `spawn' call. */
  20. int
  21. posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *file_actions,
  22. int fd, int newfd)
  23. {
  24. int maxfd = sysconf(_SC_OPEN_MAX);
  25. struct __spawn_action *rec;
  26. /* Test for the validity of the file descriptor. */
  27. if (fd < 0 || newfd < 0 || fd >= maxfd || newfd >= maxfd)
  28. return EBADF;
  29. /* Allocate more memory if needed. */
  30. if (file_actions->__used == file_actions->__allocated
  31. && __posix_spawn_file_actions_realloc (file_actions) != 0)
  32. /* This can only mean we ran out of memory. */
  33. return ENOMEM;
  34. /* Add the new value. */
  35. rec = &file_actions->__actions[file_actions->__used];
  36. rec->tag = spawn_do_dup2;
  37. rec->action.dup2_action.fd = fd;
  38. rec->action.dup2_action.newfd = newfd;
  39. /* Account for the new entry. */
  40. ++file_actions->__used;
  41. return 0;
  42. }