2fe8fb192f
There is important information about booting non-ack images in docs/UPDATING. ack/aout-format images can't be built any more, and booting clang/ELF-format ones is a little different. Updating to the new boot monitor is recommended. Changes in this commit: . drop boot monitor -> allowing dropping ack support . facility to copy ELF boot files to /boot so that old boot monitor can still boot fairly easily, see UPDATING . no more ack-format libraries -> single-case libraries . some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases . drop several ack toolchain commands, but not all support commands (e.g. aal is gone but acksize is not yet). . a few libc files moved to netbsd libc dir . new /bin/date as minix date used code in libc/ . test compile fix . harmonize includes . /usr/lib is no longer special: without ack, /usr/lib plays no kind of special bootstrapping role any more and bootstrapping is done exclusively through packages, so releases depend even less on the state of the machine making them now. . rename nbsd_lib* to lib* . reduce mtree
190 lines
4.7 KiB
Groff
190 lines
4.7 KiB
Groff
.\" $NetBSD: clock_settime.2,v 1.20 2009/03/11 13:39:14 joerg Exp $
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.\"
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.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
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.\" All rights reserved.
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.\"
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.\" This code is derived from software contributed to The NetBSD Foundation
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.\" by Klaus Klein.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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.\" POSSIBILITY OF SUCH DAMAGE.
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.\"
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.Dd February 11, 1999
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.Dt CLOCK_SETTIME 2
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.Os
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.Sh NAME
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.Nm clock_settime ,
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.Nm clock_gettime ,
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.Nm clock_getres
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.Nd clock and timer functions
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.Sh LIBRARY
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.Lb libc
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.Sh SYNOPSIS
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.In time.h
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.Ft int
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.Fn clock_settime "clockid_t clock_id" "const struct timespec *tp"
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.Ft int
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.Fn clock_gettime "clockid_t clock_id" "struct timespec *tp"
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.Ft int
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.Fn clock_getres "clockid_t clock_id" "struct timespec *res"
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.Sh DESCRIPTION
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The
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.Fn clock_settime
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function sets the clock identified by
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.Fa clock_id
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to the absolute time specified by
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.Fa tp .
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If the time specified by
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.Fa tp
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is not a multiple of the resolution of the clock,
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.Fa tp
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is truncated to a multiple of the resolution.
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.Pp
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The
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.Fn clock_gettime
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function stores the time of the clock identified by
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.Fa clock_id
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into the location specified by
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.Fa tp .
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.Pp
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The
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.Fn clock_getres
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function stores the resolution of the clock identified by
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.Fa clock_id
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into the location specified by
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.Fa res ,
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unless
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.Fa res
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is
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.Dv NULL .
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.Pp
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A
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.Fa clock_id
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of
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.Dv CLOCK_REALTIME
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identifies the realtime clock for the system.
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For this clock, the values specified by
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.Fn clock_settime
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and obtained by
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.Fn clock_gettime
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represent the amount of time (in seconds and nanoseconds)
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since 00:00 Universal Coordinated Time, January 1, 1970.
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.Pp
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A
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.Fa clock_id
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of
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.Dv CLOCK_MONOTONIC
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identifies a clock that increases at a steady rate (monotonically).
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This clock
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is not affected by calls to
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.Xr adjtime 2
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and
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.Xr settimeofday 2
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and will
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fail with an
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.Er EINVAL
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error if it's the clock specified in a call to
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.Fn clock_settime .
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The origin of the clock is unspecified.
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.Pp
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If the calling user is not the super-user, then the
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.Fn clock_settime
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function in the standard C library will try to use the
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.Xr clockctl 4
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device if present, thus making possible for non privileged users to
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set the system time.
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If
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.Xr clockctl 4
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is not present or not accessible, then
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.Fn clock_settime
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reverts to the
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.Fn clock_settime
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system call, which is restricted to the super user.
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.Sh RETURN VALUES
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A value of 0 is returned on success.
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Otherwise, a value of \-1 is returned and
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.Va errno
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is set to indicate the error.
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.Sh ERRORS
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The
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.Fn clock_settime ,
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.Fn clock_gettime
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and
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.Fn clock_getres
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functions will fail if:
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.Bl -tag -width Er
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.It Bq Er EINVAL
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The
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.Fa clock_id
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argument does not specify a known clock.
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.It Bq Er ENOSYS
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The function is not supported by this implementation.
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.El
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.Pp
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The
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.Fn clock_settime
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function will fail if:
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.Bl -tag -width Er
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.It Bq Er EINVAL
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The
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.Fa tp
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argument is outside the range for the specified clock,
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.Fa clock_id .
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.It Bq Er EINVAL
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The
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.Fa tp
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argument specified a nanosecond value less than zero of greater than or equal
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1000 million.
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.It Bq Er EINVAL
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The
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.Fa clock_id
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argument is a clock that can not be adjusted.
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.It Bq Er EPERM
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The
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calling process does not have the appropriate privilege to set the specified
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clock,
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.Fa clock_id .
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.El
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.Pp
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The
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.Fn clock_gettime
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function will fail if:
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.Bl -tag -width Er
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.It Bq Er EFAULT
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The
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.Fa tp
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argument specifies an address that is not a valid part of the process address
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space.
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.El
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.Sh SEE ALSO
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.Xr ctime 3 ,
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.Xr time 3 ,
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.\" .Xr timer_gettime 3 ,
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.Xr clockctl 4
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.Sh STANDARDS
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The
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.Fn clock_settime ,
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.Fn clock_gettime
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and
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.Fn clock_getres
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functions conform to
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.St -p1003.1b-93 .
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