1 /* Compatibility definitions for System V `poll' interface. 2 Copyright (C) 1994,1996-2001,2004-2006,2012 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <http://www.gnu.org/licenses/>. */ 18 19 #ifndef _SYS_POLL_H 20 #define _SYS_POLL_H 1 21 22 #include <features.h> 23 24 /* Get the platform dependent bits of `poll'. */ 25 #include <bits/poll.h> 26 #ifdef __USE_GNU 27 /* Get the __sigset_t definition. */ 28 # include <bits/sigset.h> 29 /* Get the timespec definition. */ 30 # define __need_timespec 31 # include <time.h> 32 #endif 33 34 35 /* Type used for the number of file descriptors. */ 36 typedef unsigned long int nfds_t; 37 38 /* Data structure describing a polling request. */ 39 struct pollfd 40 { 41 int fd; /* File descriptor to poll. */ 42 short int events; /* Types of events poller cares about. */ 43 short int revents; /* Types of events that actually occurred. */ 44 }; 45 46 47 __BEGIN_DECLS 48 49 /* Poll the file descriptors described by the NFDS structures starting at 50 FDS. If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for 51 an event to occur; if TIMEOUT is -1, block until an event occurs. 52 Returns the number of file descriptors with events, zero if timed out, 53 or -1 for errors. 54 55 This function is a cancellation point and therefore not marked with 56 __THROW. */ 57 extern int poll (struct pollfd *__fds, nfds_t __nfds, int __timeout); 58 59 #ifdef __USE_GNU 60 /* Like poll, but before waiting the threads signal mask is replaced 61 with that specified in the fourth parameter. For better usability, 62 the timeout value is specified using a TIMESPEC object. 63 64 This function is a cancellation point and therefore not marked with 65 __THROW. */ 66 extern int ppoll (struct pollfd *__fds, nfds_t __nfds, 67 const struct timespec *__timeout, 68 const __sigset_t *__ss); 69 #endif 70 71 __END_DECLS 72 73 74 /* Define some inlines helping to catch common problems. */ 75 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function 76 # include <bits/poll2.h> 77 #endif 78 79 #endif /* sys/poll.h */ 80