glibc/io/sys/poll.h

79 lines
2.6 KiB
C

/* Compatibility definitions for System V `poll' interface.
Copyright (C) 1994-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _SYS_POLL_H
#define _SYS_POLL_H 1
#include <features.h>
/* Get the platform dependent bits of `poll'. */
#include <bits/poll.h>
#ifdef __USE_GNU
/* Get the __sigset_t definition. */
# include <bits/sigset.h>
/* Get the timespec definition. */
#include <bits/types/struct_timespec.h>
#endif
/* Type used for the number of file descriptors. */
typedef unsigned long int nfds_t;
/* Data structure describing a polling request. */
struct pollfd
{
int fd; /* File descriptor to poll. */
short int events; /* Types of events poller cares about. */
short int revents; /* Types of events that actually occurred. */
};
__BEGIN_DECLS
/* Poll the file descriptors described by the NFDS structures starting at
FDS. If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for
an event to occur; if TIMEOUT is -1, block until an event occurs.
Returns the number of file descriptors with events, zero if timed out,
or -1 for errors.
This function is a cancellation point and therefore not marked with
__THROW. */
extern int poll (struct pollfd *__fds, nfds_t __nfds, int __timeout);
#ifdef __USE_GNU
/* Like poll, but before waiting the threads signal mask is replaced
with that specified in the fourth parameter. For better usability,
the timeout value is specified using a TIMESPEC object.
This function is a cancellation point and therefore not marked with
__THROW. */
extern int ppoll (struct pollfd *__fds, nfds_t __nfds,
const struct timespec *__timeout,
const __sigset_t *__ss);
#endif
__END_DECLS
/* Define some inlines helping to catch common problems. */
#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
# include <bits/poll2.h>
#endif
#endif /* sys/poll.h */