poll.h 2.6 KB

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  1. /* Compatibility definitions for System V `poll' interface.
  2. Copyright (C) 1994-2017 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. #ifndef _SYS_POLL_H
  16. #define _SYS_POLL_H 1
  17. #include <features.h>
  18. /* Get the platform dependent bits of `poll'. */
  19. #include <bits/poll.h>
  20. #ifdef __USE_GNU
  21. /* Get the __sigset_t definition. */
  22. # include <bits/sigset.h>
  23. /* Get the timespec definition. */
  24. #include <bits/types/struct_timespec.h>
  25. #endif
  26. /* Type used for the number of file descriptors. */
  27. typedef unsigned long int nfds_t;
  28. /* Data structure describing a polling request. */
  29. struct pollfd
  30. {
  31. int fd; /* File descriptor to poll. */
  32. short int events; /* Types of events poller cares about. */
  33. short int revents; /* Types of events that actually occurred. */
  34. };
  35. __BEGIN_DECLS
  36. /* Poll the file descriptors described by the NFDS structures starting at
  37. FDS. If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for
  38. an event to occur; if TIMEOUT is -1, block until an event occurs.
  39. Returns the number of file descriptors with events, zero if timed out,
  40. or -1 for errors.
  41. This function is a cancellation point and therefore not marked with
  42. __THROW. */
  43. extern int poll (struct pollfd *__fds, nfds_t __nfds, int __timeout);
  44. #ifdef __USE_GNU
  45. /* Like poll, but before waiting the threads signal mask is replaced
  46. with that specified in the fourth parameter. For better usability,
  47. the timeout value is specified using a TIMESPEC object.
  48. This function is a cancellation point and therefore not marked with
  49. __THROW. */
  50. extern int ppoll (struct pollfd *__fds, nfds_t __nfds,
  51. const struct timespec *__timeout,
  52. const __sigset_t *__ss);
  53. #endif
  54. __END_DECLS
  55. /* Define some inlines helping to catch common problems. */
  56. #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
  57. # include <bits/poll2.h>
  58. #endif
  59. #endif /* sys/poll.h */