[src/trunk]: src/share/man/man9 a manpage of selrecord and selwakeup. from F...

[yamt <yamt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/eb27524991cc
branches:  trunk
changeset: 555404:eb27524991cc
user:      yamt <yamt%NetBSD.org@localhost>
date:      Sun Nov 16 15:07:25 2003 +0000

description:
a manpage of selrecord and selwakeup.  from FreeBSD.

diffstat:

 share/man/man9/Makefile    |   4 +-
 share/man/man9/selrecord.9 |  99 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 102 insertions(+), 1 deletions(-)

diffs (121 lines):

diff -r 822354a0374d -r eb27524991cc share/man/man9/Makefile
--- a/share/man/man9/Makefile   Sun Nov 16 14:56:05 2003 +0000
+++ b/share/man/man9/Makefile   Sun Nov 16 15:07:25 2003 +0000
@@ -1,4 +1,4 @@
-#       $NetBSD: Makefile,v 1.149 2003/10/21 22:01:24 hannken Exp $
+#       $NetBSD: Makefile,v 1.150 2003/11/16 15:07:25 yamt Exp $
 
 #      Makefile for section 9 (kernel function and variable) manual pages.
 
@@ -389,6 +389,8 @@
 MLINKS+=SCHED_LOCK.9 SCHED_UNLOCK.9 \
        SCHED_LOCK.9 sched_lock_idle.9 \
        SCHED_LOCK.9 sched_unlock_idle.9
+MAN+=  selrecord.9
+MLINKS+=selrecord.9 selwakeup.9
 MLINKS+=setjmp.9 longjmp.9
 MLINKS+=setrunqueue.9 remrunqueue.9 \
        setrunqueue.9 nextrunqueue.9
diff -r 822354a0374d -r eb27524991cc share/man/man9/selrecord.9
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/share/man/man9/selrecord.9        Sun Nov 16 15:07:25 2003 +0000
@@ -0,0 +1,99 @@
+.\"     $NetBSD: selrecord.9,v 1.1 2003/11/16 15:07:25 yamt Exp $
+.\"
+.\" Copyright (C) 2002 Chad David <davidc%acns.ab.ca@localhost>. 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(s), this list of conditions and the following disclaimer as
+.\"    the first lines of this file unmodified other than the possible
+.\"    addition of one or more copyright notices.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice(s), this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
+.\"
+.\" $FreeBSD: src/share/man/man9/selrecord.9,v 1.2 2002/05/30 13:29:17 ru Exp $
+.\"
+.\" FreeBSD: .Dd March 20, 2002
+.Dd November 16, 2003
+.Dt SELRECORD 9
+.Os
+.Sh NAME
+.Nm selrecord ,
+.Nm selwakeup
+.Nd "record and wakeup select requests"
+.Sh SYNOPSIS
+.In sys/param.h
+.In sys/select.h
+.Ft void
+.Fn selrecord "struct proc *selector" "struct selinfo *sip"
+.Ft void
+.Fn selwakeup "struct selinfo *sip"
+.Sh DESCRIPTION
+.Fn selrecord
+and
+.Fn selwakeup
+are the two central functions used by
+.Xr select 2 ,
+.Xr poll 2
+and the objects that are being selected on.
+They handle the task of recording which threads are waiting on which objects
+and the waking of the proper threads when an event of interest occurs on an
+object.
+.Pp
+.Fn selrecord
+records that the calling thread is interested in events related to a given
+object.
+If another thread is already waiting on the object a collision will be flagged
+in
+.Fa sip
+which will be later dealt with by
+.Fn selwakeup .
+.Pp
+.Fn selwakeup
+is called by the underlying object handling code in order to notify any waiting
+threads that an event of interest has occurred.
+If a collision has occurred,
+.Fn selwakeup
+will increment
+.Va nselcoll ,
+and wakeup all threads waiting on the global variable
+.Va selwait
+so that they can handle it.
+If the thread waiting on the object is not currently sleeping or the wait
+channel is not
+.Va selwait ,
+.Fn selwakeup
+will clear the
+.Dv L_SELECT
+flag which should be noted by
+.Xr select 2
+and
+.Xr poll 2
+when they wake up.
+.Pp
+.Fn selwakeup
+may acquire and release
+.Va sched_lock .
+.Sh SEE ALSO
+.Xr poll 2 ,
+.Xr select 2
+.Sh AUTHORS
+.An -nosplit
+This man page was written by
+.An Chad David Aq davidc%FreeBSD.org@localhost
+and
+.An Alfred Perlstein Aq alfred%FreeBSD.org@localhost .