xnu-792.tar.gz

[apple/xnu.git] / bsd / sys / poll.h

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*-
 * Copyright (c) 1997 Peter Wemm <peter@freebsd.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#ifndef _SYS_POLL_H_
#define	_SYS_POLL_H_

/*
 * This file is intended to be compatable with the traditional poll.h.
 */

/*
 * Requestable events.  If poll(2) finds any of these set, they are
 * copied to revents on return.
 */
#define	POLLIN		0x0001		/* any readable data available */
#define	POLLPRI		0x0002		/* OOB/Urgent readable data */
#define	POLLOUT		0x0004		/* file descriptor is writeable */
#define	POLLRDNORM	0x0040		/* non-OOB/URG data available */
#define	POLLWRNORM	POLLOUT		/* no write type differentiation */
#define	POLLRDBAND	0x0080		/* OOB/Urgent readable data */
#define	POLLWRBAND	0x0100		/* OOB/Urgent data can be written */

/*
 * FreeBSD extensions: polling on a regular file might return one
 * of these events (currently only supported on local filesystems).
 */
#define	POLLEXTEND	0x0200		/* file may have been extended */
#define	POLLATTRIB	0x0400		/* file attributes may have changed */
#define	POLLNLINK	0x0800		/* (un)link/rename may have happened */
#define	POLLWRITE	0x1000		/* file's contents may have changed */

/*
 * These events are set if they occur regardless of whether they were
 * requested.
 */
#define	POLLERR		0x0008		/* some poll error occurred */
#define	POLLHUP		0x0010		/* file descriptor was "hung up" */
#define	POLLNVAL	0x0020		/* requested events "invalid" */

#define	POLLSTANDARD	(POLLIN|POLLPRI|POLLOUT|POLLRDNORM|POLLRDBAND|\
			 POLLWRBAND|POLLERR|POLLHUP|POLLNVAL)

struct pollfd
{
	int     fd;
	short   events;
	short   revents;
};

typedef unsigned int nfds_t;

#if !defined(KERNEL)

#include <sys/cdefs.h>

__BEGIN_DECLS

/*
 * This is defined here (instead of <poll.h>) because this is where
 * traditional SVR4 code will look to find it.
 */
extern int poll (struct pollfd *, nfds_t, int);

__END_DECLS

#endif /* !KERNEL */

#endif /* !_SYS_POLL_H_ */