[src/trunk]: src/share/man/man3 Add timeradd(3) from FreeBSD. Needs proofread...

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

details:   https://anonhg.NetBSD.org/src/rev/b015d829b950
branches:  trunk
changeset: 751078:b015d829b950
user:      jruoho <jruoho%NetBSD.org@localhost>
date:      Sun Jan 24 11:14:04 2010 +0000

description:
Add timeradd(3) from FreeBSD. Needs proofreading.

ok wiz@

diffstat:

 share/man/man3/timeradd.3 |  119 ++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 119 insertions(+), 0 deletions(-)

diffs (123 lines):

diff -r be307ff62f95 -r b015d829b950 share/man/man3/timeradd.3
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/share/man/man3/timeradd.3 Sun Jan 24 11:14:04 2010 +0000
@@ -0,0 +1,119 @@
+.\" Copyright (c) 1999 Kelly Yancey <kbyanc%posi.net@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, 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. Neither the name of the author nor the names of any co-contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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.
+.\"
+.\" $FreeBSD: src/share/man/man3/timeradd.3,v 1.3 2003/09/08 19:57:19 ru Exp $
+.\"
+.Dd January 24, 2010
+.Dt TIMERADD 3
+.Os
+.Sh NAME
+.Nm timeradd ,
+.Nm timersub ,
+.Nm timerclear ,
+.Nm timerisset ,
+.Nm timercmp
+.Nd operations on timevals
+.Sh SYNOPSIS
+.In sys/time.h
+.Ft void
+.Fn timeradd "struct timeval *a" "struct timeval *b" "struct timeval *res"
+.Ft void
+.Fn timersub "struct timeval *a" "struct timeval *b" "struct timeval *res"
+.Ft void
+.Fn timerclear "struct timeval *tvp"
+.Ft int
+.Fn timerisset "struct timeval *tvp"
+.Ft int
+.Fn timercmp "struct timeval *a" "struct timeval *b" CMP
+.Sh DESCRIPTION
+These macros are provided for manipulating
+.Fa timeval
+structures for use with the
+.Xr gettimeofday 2
+and
+.Xr settimeofday 2
+calls.
+The structure is defined in
+.In sys/time.h
+as:
+.Bd -literal
+struct timeval {
+       time_t          tv_sec;         /* seconds */
+       suseconds_t     tv_usec;        /* and microseconds */
+};
+.Ed
+.Pp
+.Fn timeradd
+adds the time information stored in
+.Fa a
+to
+.Fa b
+and stores the resulting
+.Vt timeval
+in
+.Fa res .
+The results are simplified such that the value of
+.Fa res->tv_usec
+is always less than 1,000,000 (1 second).
+.Pp
+.Fn timersub
+subtracts the time information stored in
+.Fa b
+from
+.Fa a
+and stores the resulting
+.Vt timeval
+in
+.Fa res .
+.Pp
+.Fn timerclear
+initializes
+.Fa tvp
+to midnight (0 hour) January 1st, 1970 (the Epoch).
+.Pp
+.Fn timerisset
+returns true if
+.Fa tvp
+is set to any time value other than the Epoch.
+.Pp
+.Fn timercmp
+compares
+.Fa a
+to
+.Fa b
+using the comparison operator given in
+.Fa CMP ,
+and returns the result of that comparison.
+.Sh SEE ALSO
+.Xr gettimeofday 2
+.Sh HISTORY
+The
+.Fn timeradd
+family of macros first appeared in
+.Nx 1.1 .
+These were later ported to
+.Fx 2.2.6 .