2.11BSD/sys/h/select.h

/*-
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)select.h	8.2.1 (2.11BSD) 2000/2/28
 */

#ifndef _SYS_SELECT_H_
#define	_SYS_SELECT_H_

#include <sys/types.h>

/*
 * Select uses bit masks of file descriptors in longs.
 * These macros manipulate such bit fields (the filesystem macros use chars).
 * FD_SETSIZE may be defined by the user, but the default here
 * should be >= NOFILE (param.h).
 */
#ifndef	FD_SETSIZE
#define	FD_SETSIZE	32
#endif

typedef long	fd_mask;
#define NFDBITS	(sizeof(fd_mask) * NBBY)	/* bits per mask */

typedef	struct fd_set {
	fd_mask	fds_bits[1];
} fd_set;

#define	FD_SET(n, p)	((p)->fds_bits[(n)/NFDBITS] |= (1L << ((n) % NFDBITS)))
#define	FD_CLR(n, p)	((p)->fds_bits[(n)/NFDBITS] &= ~(1L << ((n) % NFDBITS)))
#define	FD_ISSET(n, p)	((p)->fds_bits[(n)/NFDBITS] & (1L << ((n) % NFDBITS)))
#define FD_ZERO(p)	bzero((char *)(p), sizeof(*(p)))

#ifndef KERNEL
int	select();
int	pselect();
#endif /* !KERNEL */

#endif /* !_SYS_SELECT_H_ */