poll.h 2.0 KB

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  1. /* Copyright (C) 1997, 2001 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. #ifndef _SYS_POLL_H
  15. # error "Never use <bits/poll.h> directly; include <sys/poll.h> instead."
  16. #endif
  17. /* Event types that can be polled for. These bits may be set in `events'
  18. to indicate the interesting event types; they will appear in `revents'
  19. to indicate the status of the file descriptor. */
  20. #define POLLIN 0x001 /* There is data to read. */
  21. #define POLLPRI 0x002 /* There is urgent data to read. */
  22. #define POLLOUT 0x004 /* Writing now will not block. */
  23. #ifdef __USE_XOPEN
  24. /* These values are defined in XPG4.2. */
  25. # define POLLRDNORM 0x040 /* Normal data may be read. */
  26. # define POLLRDBAND 0x080 /* Priority data may be read. */
  27. # define POLLWRNORM POLLOUT /* Writing now will not block. */
  28. # define POLLWRBAND 0x100 /* Priority data may be written. */
  29. #endif
  30. #ifdef __USE_GNU
  31. /* These are extensions for Linux. */
  32. # define POLLMSG 0x400
  33. # define POLLREMOVE 0x1000
  34. # define POLLRDHUP 0x2000
  35. #endif
  36. /* Event types always implicitly polled for. These bits need not be set in
  37. `events', but they will appear in `revents' to indicate the status of
  38. the file descriptor. */
  39. #define POLLERR 0x008 /* Error condition. */
  40. #define POLLHUP 0x010 /* Hung up. */
  41. #define POLLNVAL 0x020 /* Invalid polling request. */