1.\" Copyright (c) 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 Institute of Electrical and Electronics Engineers, Inc. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" @(#)touch.1 8.3 (Berkeley) 4/28/95 36.\" $FreeBSD$ 37.\" 38.Dd April 28, 1995 39.Dt TOUCH 1 40.Os 41.Sh NAME 42.Nm touch 43.Nd change file access and modification times 44.Sh SYNOPSIS 45.Nm 46.Op Fl acfm 47.Op Fl r Ar file 48.Op Fl t Ar [[CC]YY]MMDDhhmm[.SS] 49.Ar 50.Sh DESCRIPTION 51The 52.Nm 53utility sets the modification and access times of files to the 54current time of day. 55If the file doesn't exist, it is created with default permissions. 56.Pp 57The following options are available: 58.Bl -tag -width Ds 59.It Fl a 60Change the access time of the file. 61The modification time of the file is not changed unless the 62.Fl m 63flag is also specified. 64.It Fl c 65Do not create the file if it does not exist. 66The 67.Nm 68utility does not treat this as an error. 69No error messages are displayed and the exit value is not affected. 70.It Fl f 71Attempt to force the update, even if the file permissions do not 72currently permit it. 73.It Fl m 74Change the modification time of the file. 75The access time of the file is not changed unless the 76.Fl a 77flag is also specified. 78.It Fl r 79Use the access and modifications times from the specified file 80instead of the current time of day. 81.It Fl t 82Change the access and modification times to the specified time. 83The argument should be in the form 84.Dq [[CC]YY]MMDDhhmm[.SS] 85where each pair of letters represents the following: 86.Pp 87.Bl -tag -width Ds -compact -offset indent 88.It Ar CC 89The first two digits of the year (the century). 90.It Ar YY 91The second two digits of the year. 92If 93.Dq YY 94is specified, but 95.Dq CC 96is not, a value for 97.Dq YY 98between 69 and 99 results in a 99.Dq CC 100value of 19. 101Otherwise, a 102.Dq CC 103value of 20 is used. 104.It Ar MM 105The month of the year, from 1 to 12. 106.It Ar DD 107the day of the month, from 1 to 31. 108.It Ar hh 109The hour of the day, from 0 to 23. 110.It Ar mm 111The minute of the hour, from 0 to 59. 112.It Ar SS 113The second of the minute, from 0 to 61. 114.El 115.Pp 116If the 117.Dq CC 118and 119.Dq YY 120letter pairs are not specified, the values default to the current 121year. 122If the 123.Dq SS 124letter pair is not specified, the value defaults to 0. 125.El 126.Sh DIAGNOSTICS 127The 128.Nm 129utility exits 0 on success, and >0 if an error occurs. 130.Sh SEE ALSO 131.Xr utimes 2 132.Sh COMPATIBILITY 133The obsolescent form of 134.Nm touch , 135where a time format is specified as the first argument, is supported. 136When no 137.Fl r 138or 139.Fl t 140option is specified, there are at least two arguments, and the first 141argument is a string of digits either eight or ten characters in length, 142the first argument is interpreted as a time specification of the form 143.Dq MMDDhhmm[YY] . 144.Pp 145The 146.Dq MM , 147.Dq DD , 148.Dq hh 149and 150.Dq mm 151letter pairs are treated as their counterparts specified to the 152.Fl t 153option. 154If the 155.Dq YY 156letter pair is in the range 39 to 99, the year is set to 1939 to 1999, 157otherwise, the year is set in the 21st century. 158.Sh HISTORY 159A 160.Nm 161utility appeared in 162.At v7 . 163.Sh STANDARDS 164The 165.Nm 166utility is expected to be a superset of the 167.St -p1003.2 168specification. 169