| clocks.7 (79727) | clocks.7 (81622) |
|---|---|
| 1.\" 2.\" Copyright (c) 1996 Joerg Wunsch 3.\" 4.\" All rights reserved. 5.\" 6.\" This program is free software. 7.\" 8.\" Redistribution and use in source and binary forms, with or without --- 11 unchanged lines hidden (view full) --- 20.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 21.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" | 1.\" 2.\" Copyright (c) 1996 Joerg Wunsch 3.\" 4.\" All rights reserved. 5.\" 6.\" This program is free software. 7.\" 8.\" Redistribution and use in source and binary forms, with or without --- 11 unchanged lines hidden (view full) --- 20.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 21.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" |
| 28.\" $FreeBSD: head/share/man/man7/clocks.7 79727 2001-07-14 19:41:16Z schweikh $ | 28.\" $FreeBSD: head/share/man/man7/clocks.7 81622 2001-08-14 10:01:54Z ru $ |
| 29.\" " 30.Dd April 1, 1996 31.Os 32.Dt CLOCKS 7 33.Sh NAME 34.Nm clocks 35.Nd various system timers 36.Sh SYNOPSIS 37.Fd #include <time.h> 38.Sh DESCRIPTION 39.Ql HZ | 29.\" " 30.Dd April 1, 1996 31.Os 32.Dt CLOCKS 7 33.Sh NAME 34.Nm clocks 35.Nd various system timers 36.Sh SYNOPSIS 37.Fd #include <time.h> 38.Sh DESCRIPTION 39.Ql HZ |
| 40is not part of the application interface in BSD. | 40is not part of the application interface in 41.Bx . |
| 41.Pp 42There are many different real and virtual (timekeeping) clocks with 43different frequencies: 44.Bl -bullet -offset XXX 45.It 46The scheduling clock. This is a real clock with frequency that 47happens to be 100. It isn't available to applications. 48.It --- 53 unchanged lines hidden (view full) --- 102.Xr sysctl 3 103or by reading it from the header in the profiling data file. 104.It 105The mc14618a clock. This is a real clock with a nominal frequency of 10632768. It is divided down to give the statistic clock and the profiling 107clock. It isn't available to applications. 108.It 109The microseconds clock. This is a virtual clock with frequency | 42.Pp 43There are many different real and virtual (timekeeping) clocks with 44different frequencies: 45.Bl -bullet -offset XXX 46.It 47The scheduling clock. This is a real clock with frequency that 48happens to be 100. It isn't available to applications. 49.It --- 53 unchanged lines hidden (view full) --- 103.Xr sysctl 3 104or by reading it from the header in the profiling data file. 105.It 106The mc14618a clock. This is a real clock with a nominal frequency of 10732768. It is divided down to give the statistic clock and the profiling 108clock. It isn't available to applications. 109.It 110The microseconds clock. This is a virtual clock with frequency |
| 1101000000. It is used for most timekeeping in BSD and is exported | 1111000000. It is used for most timekeeping in 112.Bx 113and is exported |
| 111to applications in 112.Xr getrusage 2 , 113.Xr gettimeofday 2 , 114.Xr select 2 , 115.Xr getitimer 2 , 116etc... This is the clock that should normally be used | 114to applications in 115.Xr getrusage 2 , 116.Xr gettimeofday 2 , 117.Xr select 2 , 118.Xr getitimer 2 , 119etc... This is the clock that should normally be used |
| 117by BSD applications. | 120by 121.Bx 122applications. |
| 118.It 119The i8254 clock. This is a real clock/timer with a nominal frequency of 1201193182. It is divided down to give the scheduling clock. It isn't 121available to applications. 122.It 123The TSC clock (64-bit register) on fifth-generation or later x86 systems. 124This is a real clock with a frequency that is equivalent to the number of 125cycles per second of the CPU(s). --- 24 unchanged lines hidden --- | 123.It 124The i8254 clock. This is a real clock/timer with a nominal frequency of 1251193182. It is divided down to give the scheduling clock. It isn't 126available to applications. 127.It 128The TSC clock (64-bit register) on fifth-generation or later x86 systems. 129This is a real clock with a frequency that is equivalent to the number of 130cycles per second of the CPU(s). --- 24 unchanged lines hidden --- |