xref: /dragonfly/sys/sys/poll.h (revision 36a3d1d6)
1 /*-
2  * Copyright (c) 1997 Peter Wemm <peter@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD: src/sys/sys/poll.h,v 1.6.2.1 2000/08/21 12:25:58 sheldonh Exp $
29  * $DragonFly: src/sys/sys/poll.h,v 1.7 2008/01/12 06:01:27 nant Exp $
30  */
31 
32 #ifndef _SYS_POLL_H_
33 #define	_SYS_POLL_H_
34 
35 /*
36  * This file is intended to be compatible with the traditional poll.h.
37  */
38 
39 typedef	unsigned int	nfds_t;
40 
41 /*
42  * This structure is passed as an array to poll(2).
43  */
44 struct pollfd {
45 	int	fd;		/* which file descriptor to poll */
46 	short	events;		/* events we are interested in */
47 	short	revents;	/* events found on return */
48 };
49 
50 /*
51  * Requestable events.  If poll(2) finds any of these set, they are
52  * copied to revents on return.
53  * XXX Note that FreeBSD doesn't make much distinction between POLLPRI
54  * and POLLRDBAND since none of the file types have distinct priority
55  * bands - and only some have an urgent "mode".
56  * XXX Note POLLIN isn't really supported in true SVSV terms.  Under SYSV
57  * POLLIN includes all of normal, band and urgent data.  Most poll handlers
58  * on FreeBSD only treat it as "normal" data.
59  */
60 #define	POLLIN		0x0001		/* any readable data available */
61 #define	POLLPRI		0x0002		/* OOB/Urgent readable data */
62 #define	POLLOUT		0x0004		/* file descriptor is writeable */
63 #define	POLLRDNORM	0x0040		/* non-OOB/URG data available */
64 #define	POLLWRNORM	POLLOUT		/* no write type differentiation */
65 #define	POLLRDBAND	0x0080		/* OOB/Urgent readable data */
66 #define	POLLWRBAND	0x0100		/* OOB/Urgent data can be written */
67 
68 /*
69  * These events are set if they occur regardless of whether they were
70  * requested.
71  */
72 #define	POLLERR		0x0008		/* some poll error occurred */
73 #define	POLLHUP		0x0010		/* file descriptor was "hung up" */
74 #define	POLLNVAL	0x0020		/* requested events "invalid" */
75 
76 #define	POLLSTANDARD	(POLLIN|POLLPRI|POLLOUT|POLLRDNORM|POLLRDBAND|\
77 			 POLLWRBAND|POLLERR|POLLHUP|POLLNVAL)
78 
79 /*
80  * Request that poll() wait forever.
81  * XXX in SYSV, this is defined in stropts.h, which is not included
82  * by poll.h.
83  */
84 #define	INFTIM		(-1)
85 
86 #ifndef _KERNEL
87 
88 #include <sys/cdefs.h>
89 
90 __BEGIN_DECLS
91 /*
92  * XXX logically, poll() should be declared in <poll.h>, but SVR4 at
93  * least has it here in <sys/poll.h>.
94  */
95 int	poll (struct pollfd *, nfds_t, int);
96 __END_DECLS
97 
98 #endif /* !_KERNEL */
99 
100 #endif /* !_SYS_POLL_H_ */
101