diff options
Diffstat (limited to 'share/man/man9/time.9')
-rw-r--r-- | share/man/man9/time.9 | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/share/man/man9/time.9 b/share/man/man9/time.9 new file mode 100644 index 0000000..4a2b2f7 --- /dev/null +++ b/share/man/man9/time.9 @@ -0,0 +1,115 @@ +.\" $NetBSD: time.9,v 1.1 1995/11/25 21:24:53 perry Exp $ +.\" +.\" Copyright (c) 1994 Christopher G. Demetriou +.\" 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 Christopher G. Demetriou +.\" for the NetBSD Project. +.\" 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 ``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 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. +.\" +.\" $FreeBSD$ +.\" +.Dd September 17, 2004 +.Dt TIME 9 +.Os +.Sh NAME +.Nm boottime , +.Nm time_second , +.Nm time_uptime +.Nd system time variables +.Sh SYNOPSIS +.In sys/time.h +.Pp +.Vt extern struct timeval boottime ; +.Vt extern time_t time_second ; +.Vt extern time_t time_uptime ; +.Sh DESCRIPTION +The +.Va boottime +variable holds the system boot time. +.Pp +The +.Va time_second +variable is the system's +.Dq wall time +clock to the second. +.Pp +The +.Va time_uptime +variable is the number of seconds since boot. +.Pp +The +.Xr bintime 9 , +.Xr getbintime 9 , +.Xr microtime 9 , +.Xr getmicrotime 9 , +.Xr nanotime 9 , +and +.Xr getnanotime 9 +functions can be used to get the current time more accurately and in an +atomic manner. +Similarly, the +.Xr binuptime 9 , +.Xr getbinuptime 9 , +.Xr microuptime 9 , +.Xr getmicrouptime 9 , +.Xr nanouptime 9 , +and +.Xr getnanouptime 9 +functions can be used to get the time elapse since boot more accurately +and in an atomic manner. +The +.Va boottime +variable may be read and written without special precautions. +.Sh SEE ALSO +.Xr clock_settime 2 , +.Xr ntp_adjtime 2 , +.Xr settimeofday 2 , +.Xr bintime 9 , +.Xr binuptime 9 , +.Xr getbintime 9 , +.Xr getbinuptime 9 , +.Xr getmicrotime 9 , +.Xr getmicrouptime 9 , +.Xr getnanotime 9 , +.Xr getnanouptime 9 , +.Xr microtime 9 , +.Xr microuptime 9 , +.Xr nanotime 9 , +.Xr nanouptime 9 +.Rs +.%A "Poul-Henning Kamp" +.%T "Timecounters: Efficient and precise timekeeping in SMP kernels" +.%J "Proceedings of EuroBSDCon 2002, Amsterdam" +.%O /usr/share/doc/papers/timecounter.ascii.gz +.Re +.Rs +.%A "Marshall Kirk McKusick" +.%A "George V. Neville-Neil" +.%B "The Design and Implementation of the FreeBSD Operating System" +.%D "July 2004" +.%I "Addison-Wesley" +.%P "57-61,65-66" +.Re |