1.\" $NetBSD: touch.1,v 1.14 2002/02/08 01:36:35 ross Exp $ 2.\" 3.\" Copyright (c) 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" the Institute of Electrical and Electronics Engineers, Inc. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the University of 20.\" California, Berkeley and its contributors. 21.\" 4. Neither the name of the University nor the names of its contributors 22.\" may be used to endorse or promote products derived from this software 23.\" without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35.\" SUCH DAMAGE. 36.\" 37.\" @(#)touch.1 8.3 (Berkeley) 4/28/95 38.\" 39.Dd April 28, 1995 40.Dt TOUCH 1 41.Os 42.Sh NAME 43.Nm touch 44.Nd change file access and modification times 45.Sh SYNOPSIS 46.Nm 47.Op Fl acfhm 48.Op Fl r Ar file 49.Op Fl t Ar [[CC]YY]MMDDhhmm[.SS] 50.Ar file ... 51.Sh DESCRIPTION 52The 53.Nm 54utility sets the modification and access times of files to the 55current time of day. 56If the file doesn't exist, it is created with default permissions. 57.Pp 58The following options are available: 59.Bl -tag -width Ds 60.It Fl a 61Change the access time of the file. 62The modification time of the file is not changed unless the 63.Fl m 64flag is also specified. 65.It Fl c 66Do not create the file if it does not exist. 67The 68.Nm 69utility does not treat this as an error. 70No error messages are displayed and the exit value is not affected. 71.It Fl f 72Attempt to force the update, even if the file permissions do not 73currently permit it. 74.It Fl h 75If 76.Ar file 77is a symbolic link, access and/or modification time of the link is changed. 78This option implies 79.Fl c . 80.It Fl m 81Change the modification time of the file. 82The access time of the file is not changed unless the 83.Fl a 84flag is also specified. 85.It Fl r 86Use the access and modifications times from the specified file 87instead of the current time of day. 88.It Fl t 89Change the access and modification times to the specified time. 90The argument should be in the form 91.Dq [[CC]YY]MMDDhhmm[.SS] 92where each pair of letters represents the following: 93.Pp 94.Bl -tag -width Ds -compact -offset indent 95.It Ar CC 96The first two digits of the year (the century). 97.It Ar YY 98The second two digits of the year. 99If 100.Dq YY 101is specified, but 102.Dq CC 103is not, a value for 104.Dq YY 105between 69 and 99 results in a 106.Dq CC 107value of 19. 108Otherwise, a 109.Dq CC 110value of 20 is used. 111.It Ar MM 112The month of the year, from 1 to 12. 113.It Ar DD 114The day of the month, from 1 to 31. 115.It Ar hh 116The hour of the day, from 0 to 23. 117.It Ar mm 118The minute of the hour, from 0 to 59. 119.It Ar SS 120The second of the minute, from 0 to 61. 121.El 122.Pp 123If the 124.Dq CC 125and 126.Dq YY 127letter pairs are not specified, the values default to the current 128year. 129If the 130.Dq SS 131letter pair is not specified, the value defaults to 0. 132.El 133.Pp 134The 135.Nm 136utility exits 0 on success, and \*[Gt]0 if an error occurs. 137.Sh SEE ALSO 138.Xr utimes 2 139.Sh COMPATIBILITY 140The obsolescent form of 141.Nm "" , 142where a time format is specified as the first argument, is supported. 143When no 144.Fl r 145or 146.Fl t 147option is specified, there are at least two arguments, and the first 148argument is a string of digits either eight or ten characters in length, 149the first argument is interpreted as a time specification of the form 150.Dq MMDDhhmm[YY] . 151.Pp 152The 153.Dq MM , 154.Dq DD , 155.Dq hh 156and 157.Dq mm 158letter pairs are treated as their counterparts specified to the 159.Fl t 160option. 161If the 162.Dq YY 163letter pair is in the range 69 to 99, the year is set to 1969 to 1999, 164otherwise, the year is set in the 21st century. 165.Sh STANDARDS 166The 167.Nm 168utility is expected to be a superset of the 169.St -p1003.2 170specification. 171.Sh HISTORY 172A 173.Nm 174utility appeared in 175.At v7 . 176.Sh BUGS 177A symbolic link can't be a reference file of access and/or modification time. 178