66 lines
2.5 KiB
C
66 lines
2.5 KiB
C
/* Compatibility definitions for System V `poll' interface.
|
|
Copyright (C) 1994 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 Library General Public License as
|
|
published by the Free Software Foundation; either version 2 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
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If
|
|
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
|
|
Cambridge, MA 02139, USA. */
|
|
|
|
#ifndef _SYS_POLL_H
|
|
#define _SYS_POLL_H
|
|
|
|
#include <sys/cdefs.h>
|
|
|
|
/* 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. */
|
|
};
|
|
|
|
/* Event types that can be polled for. These bits may be set in `events'
|
|
to indicate the interesting event types; they will appear in `revents'
|
|
to indicate the status of the file descriptor. */
|
|
#define POLLIN 01 /* There is data to read. */
|
|
#define POLLPRI 02 /* There is urgent data to read. */
|
|
#define POLLOUT 04 /* Writing now will not block. */
|
|
|
|
/* Event types always implicitly polled for. These bits need not be set in
|
|
`events', but they will appear in `revents' to indicate the status of
|
|
the file descriptor. */
|
|
#define POLLERR 010 /* Error condition. */
|
|
#define POLLHUP 020 /* Hung up. */
|
|
#define POLLNVAL 040 /* Invalid polling request. */
|
|
|
|
/* Canonical number of polling requests to read in at a time in poll. */
|
|
#define NPOLLFILE 30
|
|
|
|
|
|
__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. */
|
|
|
|
extern int poll __P ((struct pollfd *__fds, unsigned long int __nfds,
|
|
int __timeout));
|
|
|
|
__END_DECLS
|
|
|
|
#endif /* sys/poll.h */
|
|
|