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Diffstat (limited to 'lib/libc/sys/clock_gettime.2')
-rw-r--r-- | lib/libc/sys/clock_gettime.2 | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/lib/libc/sys/clock_gettime.2 b/lib/libc/sys/clock_gettime.2 deleted file mode 100644 index d620ed0f03f2..000000000000 --- a/lib/libc/sys/clock_gettime.2 +++ /dev/null @@ -1,196 +0,0 @@ -.\" $OpenBSD: clock_gettime.2,v 1.4 1997/05/08 20:21:16 kstailey Exp $ -.\" -.\" Copyright (c) 1980, 1991, 1993 -.\" The Regents of the University of California. 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 University nor the names of its contributors -.\" may be used to endorse or promote products derived from this software -.\" without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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. -.\" -.\" $FreeBSD$ -.\" -.Dd July 1, 2021 -.Dt CLOCK_GETTIME 2 -.Os -.Sh NAME -.Nm clock_gettime , -.Nm clock_settime , -.Nm clock_getres -.Nd get/set/calibrate date and time -.Sh LIBRARY -.Lb libc -.Sh SYNOPSIS -.In time.h -.Ft int -.Fn clock_gettime "clockid_t clock_id" "struct timespec *tp" -.Ft int -.Fn clock_settime "clockid_t clock_id" "const struct timespec *tp" -.Ft int -.Fn clock_getres "clockid_t clock_id" "struct timespec *tp" -.Sh DESCRIPTION -The -.Fn clock_gettime -and -.Fn clock_settime -system calls allow the calling process to retrieve or set the value -used by a clock which is specified by -.Fa clock_id . -.Pp -The -.Fa clock_id -argument can be a value obtained from -.Xr clock_getcpuclockid 3 -or -.Xr pthread_getcpuclockid 3 -as well as the following values: -.Pp -.Bl -tag -width indent -compact -.It Dv CLOCK_REALTIME -.It Dv CLOCK_REALTIME_PRECISE -.It Dv CLOCK_REALTIME_FAST -.It Dv CLOCK_REALTIME_COARSE -Increments as a wall clock should. -.It Dv CLOCK_MONOTONIC -.It Dv CLOCK_MONOTONIC_PRECISE -.It Dv CLOCK_MONOTONIC_FAST -.It Dv CLOCK_MONOTONIC_COARSE -Increments in SI seconds. -.It Dv CLOCK_UPTIME -.It Dv CLOCK_UPTIME_PRECISE -.It Dv CLOCK_UPTIME_FAST -.It Dv CLOCK_BOOTTIME -Starts at zero when the kernel boots and increments -monotonically in SI seconds while the machine is running. -.It Dv CLOCK_VIRTUAL -Increments only when -the CPU is running in user mode on behalf of the calling process. -.It Dv CLOCK_PROF -Increments when the CPU is running in user or kernel mode. -.It Dv CLOCK_SECOND -Returns the current second without performing a full time counter -query, using an in-kernel cached value of the current second. -.It Dv CLOCK_PROCESS_CPUTIME_ID -Returns the execution time of the calling process. -.It Dv CLOCK_THREAD_CPUTIME_ID -Returns the execution time of the calling thread. -.El -.Pp -The clock IDs -.Fa CLOCK_REALTIME_FAST , -.Fa CLOCK_MONOTONIC_FAST , -.Fa CLOCK_UPTIME_FAST -are analogs of corresponding IDs without _FAST suffix but do not perform -a full time counter query, so their accuracy is one timer tick. -Similarly, -.Fa CLOCK_REALTIME_PRECISE , -.Fa CLOCK_MONOTONIC_PRECISE , -.Fa CLOCK_UPTIME_PRECISE -are used to get the most exact value as possible, at the expense of -execution time. -The clock IDs -.Fa CLOCK_REALTIME_COARSE , -.Fa CLOCK_MONOTONIC_COARSE -are aliases of corresponding IDs with _FAST suffix for compatibility with other -systems. -Finally, -.Dv CLOCK_BOOTTIME -is an alias for -.Dv CLOCK_UPTIME -for compatibility with other systems. -.Pp -The structure pointed to by -.Fa tp -is defined in -.In sys/timespec.h -as: -.Bd -literal -struct timespec { - time_t tv_sec; /* seconds */ - long tv_nsec; /* and nanoseconds */ -}; -.Ed -.Pp -Only the super-user may set the time of day, using only -.Fa CLOCK_REALTIME . -If the system securelevel is greater than 1 (see -.Xr init 8 ) , -the time may only be advanced. -This limitation is imposed to prevent a malicious super-user -from setting arbitrary time stamps on files. -The system time can still be adjusted backwards using the -.Xr adjtime 2 -system call even when the system is secure. -.Pp -The resolution (granularity) of a clock is returned by the -.Fn clock_getres -system call. -This value is placed in a (non-NULL) -.Fa *tp . -.Sh RETURN VALUES -.Rv -std -.Sh ERRORS -The following error codes may be set in -.Va errno : -.Bl -tag -width Er -.It Bq Er EINVAL -The -.Fa clock_id -or -.Fa timespec -argument -was not a valid value. -.It Bq Er EPERM -A user other than the super-user attempted to set the time. -.El -.Sh SEE ALSO -.Xr date 1 , -.Xr adjtime 2 , -.Xr clock_getcpuclockid 3 , -.Xr ctime 3 , -.Xr pthread_getcpuclockid 3 -.Sh STANDARDS -The -.Fn clock_gettime , -.Fn clock_settime , -and -.Fn clock_getres -system calls conform to -.St -p1003.1b-93 . -The clock IDs -.Fa CLOCK_REALTIME_FAST , -.Fa CLOCK_REALTIME_PRECISE , -.Fa CLOCK_MONOTONIC_FAST , -.Fa CLOCK_MONOTONIC_PRECISE , -.Fa CLOCK_UPTIME , -.Fa CLOCK_UPTIME_FAST , -.Fa CLOCK_UPTIME_PRECISE , -.Fa CLOCK_SECOND -are FreeBSD extensions to the POSIX interface. -.Sh HISTORY -The -.Fn clock_gettime , -.Fn clock_settime , -and -.Fn clock_getres -system calls first appeared in -.Fx 3.0 . |