1 /* Compatibility definitions for System V `poll' interface. 2 Copyright (C) 1994-2022 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 <https://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 # include <bits/types/__sigset_t.h> 28 # include <bits/types/struct_timespec.h> 29 #endif 30 31 32 /* Type used for the number of file descriptors. */ 33 typedef unsigned long int nfds_t; 34 35 /* Data structure describing a polling request. */ 36 struct pollfd 37 { 38 int fd; /* File descriptor to poll. */ 39 short int events; /* Types of events poller cares about. */ 40 short int revents; /* Types of events that actually occurred. */ 41 }; 42 43 44 __BEGIN_DECLS 45 46 /* Poll the file descriptors described by the NFDS structures starting at 47 FDS. If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for 48 an event to occur; if TIMEOUT is -1, block until an event occurs. 49 Returns the number of file descriptors with events, zero if timed out, 50 or -1 for errors. 51 52 This function is a cancellation point and therefore not marked with 53 __THROW. */ 54 extern int poll (struct pollfd *__fds, nfds_t __nfds, int __timeout) 55 __fortified_attr_access (__write_only__, 1, 2); 56 57 #ifdef __USE_GNU 58 /* Like poll, but before waiting the threads signal mask is replaced 59 with that specified in the fourth parameter. For better usability, 60 the timeout value is specified using a TIMESPEC object. 61 62 This function is a cancellation point and therefore not marked with 63 __THROW. */ 64 extern int ppoll (struct pollfd *__fds, nfds_t __nfds, 65 const struct timespec *__timeout, 66 const __sigset_t *__ss) 67 __fortified_attr_access (__write_only__, 1, 2); 68 69 # ifdef __USE_TIME_BITS64 70 # ifdef __REDIRECT 71 extern int __REDIRECT (ppoll, (struct pollfd *__fds, nfds_t __nfds, 72 const struct timespec *__timeout, 73 const __sigset_t *__ss), 74 __ppoll64) 75 __fortified_attr_access (__write_only__, 1, 2); 76 # else 77 # define ppoll __ppoll64 78 # endif 79 # endif 80 #endif 81 82 __END_DECLS 83 84 85 /* Define some inlines helping to catch common problems. */ 86 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function 87 # include <bits/poll2.h> 88 #endif 89 90 #endif /* sys/poll.h */ 91