1.\" Copyright (c) 1989, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)time.3 8.1 (Berkeley) 6/4/93 37.\" $FreeBSD$ 38.\" 39.Dd July 18, 2003 40.Dt TIME 3 41.Os 42.Sh NAME 43.Nm time 44.Nd get time of day 45.Sh LIBRARY 46.Lb libc 47.Sh SYNOPSIS 48.In time.h 49.Ft time_t 50.Fn time "time_t *tloc" 51.Sh DESCRIPTION 52The 53.Fn time 54function 55returns the value of time in seconds since 0 hours, 0 minutes, 560 seconds, January 1, 1970, Coordinated Universal Time. 57If an error occurs, 58.Fn time 59returns the value 60.Po Vt time_t Pc Ns \-1 . 61.Pp 62The return value is also stored in 63.No \&* Ns Va tloc , 64provided that 65.Va tloc 66is non-null. 67.Sh ERRORS 68The 69.Fn time 70function may fail for any of the reasons described in 71.Xr gettimeofday 2 . 72.Sh SEE ALSO 73.Xr gettimeofday 2 , 74.Xr ctime 3 75.Sh STANDARDS 76The 77.Nm 78function conforms to 79.St -p1003.1-2001 . 80.Sh BUGS 81Neither 82.St -isoC-99 83nor 84.St -p1003.1-2001 85requires 86.Fn time 87to set 88.Va errno 89on failure; thus, it is impossible for an application to distinguish 90the valid time value \-1 (representing the last UTC second of 1969) 91from the error return value. 92.Pp 93Systems conforming to earlier versions of the C and 94.Tn POSIX 95standards (including older versions of 96.Fx ) 97did not set 98.No \&* Ns Va tloc 99in the error case. 100.Sh HISTORY 101A 102.Fn time 103function appeared in 104.At v6 . 105