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+.\" Copyright (c) 1989, 1991, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the American National Standards Committee X3, on Information
+.\" Processing Systems.
+.\"
+.\" 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.
+.\"
+.Dd April 14, 2022
+.Dt TIME 3
+.Os
+.Sh NAME
+.Nm time
+.Nd get time of day
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In time.h
+.Ft time_t
+.Fn time "time_t *tloc"
+.Sh DESCRIPTION
+The
+.Fn time
+function
+returns the value of time in seconds since 0 hours, 0 minutes,
+0 seconds, January 1, 1970, Coordinated Universal Time (UTC).
+If an error occurs,
+.Fn time
+returns the value
+.Po Vt time_t Pc Ns \-1 .
+.Pp
+The return value is also stored in
+.No \&* Ns Va tloc ,
+provided that
+.Va tloc
+is non-null.
+.Sh ERRORS
+The
+.Fn time
+function may fail for any of the reasons described in
+.Xr clock_gettime 2 .
+.Sh SEE ALSO
+.Xr clock_gettime 2 ,
+.Xr gettimeofday 2 ,
+.Xr ctime 3
+.Sh STANDARDS
+The
+.Nm
+function conforms to
+.St -p1003.1-2008 .
+.Sh HISTORY
+The
+.Fn time
+system call first appeared in
+.At v1 .
+Through the
+.At v3 ,
+it returned 60 Hz ticks since an epoch that changed occasionally, because it
+was a 32-bit value that overflowed in a little over 2 years.
+.Pp
+In
+.At v4
+the granularity of the return value was reduced to whole seconds,
+delaying the aforementioned overflow until 2038.
+.Pp
+.At v7
+introduced the
+.Fn ftime
+system call, which returned time at a millisecond level,
+though retained the
+.Fn gtime
+system call (exposed as
+.Fn time
+in userland).
+.Fn time
+could have been implemented as a wrapper around
+.Fn ftime ,
+but that wasn't done.
+.Pp
+.Bx 4.1c
+implemented a higher-precision time function
+.Fn gettimeofday
+to replace
+.Fn ftime
+and reimplemented
+.Fn time
+in terms of that.
+.Pp
+Since
+.Fx 9
+the implementation of
+.Fn time
+uses
+.Fn clock_gettime "CLOCK_SECOND"
+instead of
+.Fn gettimeofday
+for performance reasons.
+.Sh BUGS
+Neither
+.St -isoC-99
+nor
+.St -p1003.1-2001
+requires
+.Fn time
+to set
+.Va errno
+on failure; thus, it is impossible for an application to distinguish
+the valid time value \-1 (representing the last UTC second of 1969)
+from the error return value.
+.Pp
+Systems conforming to earlier versions of the C and POSIX
+standards (including older versions of
+.Fx )
+did not set
+.No \&* Ns Va tloc
+in the error case.