xref: /freebsd/usr.bin/touch/touch.1 (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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 A Ar [-][[hh]mm]SS
47.Op Fl acfhm
48.Op Fl r Ar file
49.Op Fl t Ar [[CC]YY]MMDDhhmm[.SS]
50.Ar
51.Sh DESCRIPTION
52The
53.Nm
54utility sets the modification and access times of files.
55If any file does not exist, it is created with default permissions.
56.Pp
57By default,
58.Nm
59changes both modification and access times.  The
60.Fl a
61and
62.Fl m
63flags may be used to select the access time or the modification time
64individually.
65Selecting both is equivalent to the default.
66By default, the timestamps are set to the current time.
67The
68.Fl t
69flag explicitly specifies a different time, and the
70.Fl r
71flag specifies to set the times those of the specified file.
72The
73.Fl A
74flag adjusts the values by a specified amount.
75.Pp
76The following options are available:
77.Bl -tag -width Ds
78.It Fl A
79Adjust the access and modification time stamps for the file by the
80specified value.
81This flag is intended for use in modifying files with incorrectly set
82time stamps.
83.Pp
84The argument is of the form
85.Dq [-][[hh]mm]SS
86where each pair of letters represents the following:
87.Pp
88.Bl -tag -width Ds -compact -offset indent
89.It Ar -
90Make the adjustment negative: the new time stamp is set to be before
91the old one.
92.It Ar hh
93The number of hours, from 00 to 99.
94.It Ar mm
95The number of minutes, from 00 to 59.
96.It Ar SS
97The number of seconds, from 00 to 59.
98.El
99.Pp
100The
101.Fl A
102flag implies the
103.Fl c
104flag: if any file specified does not exist, it will be silently ignored.
105.It Fl a
106Change the access time of the file.
107The modification time of the file is not changed unless the
108.Fl m
109flag is also specified.
110.It Fl c
111Do not create the file if it does not exist.
112The
113.Nm
114utility does not treat this as an error.
115No error messages are displayed and the exit value is not affected.
116.It Fl f
117Attempt to force the update, even if the file permissions do not
118currently permit it.
119.It Fl h
120If the file is a symbolic link, change the times of the link
121itself rather than the file that the link points to.
122Note that
123.Fl h
124implies
125.Fl c
126and thus will not create any new files.
127.It Fl m
128Change the modification time of the file.
129The access time of the file is not changed unless the
130.Fl a
131flag is also specified.
132.It Fl r
133Use the access and modifications times from the specified file
134instead of the current time of day.
135.It Fl t
136Change the access and modification times to the specified time instead
137of the current time of day.
138The argument is of the form
139.Dq [[CC]YY]MMDDhhmm[.SS]
140where each pair of letters represents the following:
141.Pp
142.Bl -tag -width Ds -compact -offset indent
143.It Ar CC
144The first two digits of the year (the century).
145.It Ar YY
146The second two digits of the year.
147If
148.Dq YY
149is specified, but
150.Dq CC
151is not, a value for
152.Dq YY
153between 69 and 99 results in a
154.Dq CC
155value of 19.
156Otherwise, a
157.Dq CC
158value of 20 is used.
159.It Ar MM
160The month of the year, from 01 to 12.
161.It Ar DD
162the day of the month, from 01 to 31.
163.It Ar hh
164The hour of the day, from 00 to 23.
165.It Ar mm
166The minute of the hour, from 00 to 59.
167.It Ar SS
168The second of the minute, from 00 to 61.
169.El
170.Pp
171If the
172.Dq CC
173and
174.Dq YY
175letter pairs are not specified, the values default to the current
176year.
177If the
178.Dq SS
179letter pair is not specified, the value defaults to 0.
180.El
181.Sh EXIT STATUS
182.Ex -std
183.Sh COMPATIBILITY
184The obsolescent form of
185.Nm ,
186where a time format is specified as the first argument, is supported.
187When no
188.Fl r
189or
190.Fl t
191option is specified, there are at least two arguments, and the first
192argument is a string of digits either eight or ten characters in length,
193the first argument is interpreted as a time specification of the form
194.Dq MMDDhhmm[YY] .
195.Pp
196The
197.Dq MM ,
198.Dq DD ,
199.Dq hh
200and
201.Dq mm
202letter pairs are treated as their counterparts specified to the
203.Fl t
204option.
205If the
206.Dq YY
207letter pair is in the range 39 to 99, the year is set to 1939 to 1999,
208otherwise, the year is set in the 21st century.
209.Sh SEE ALSO
210.Xr utimes 2
211.Sh STANDARDS
212The
213.Nm
214utility is expected to be a superset of the
215.St -p1003.2
216specification.
217.Sh HISTORY
218A
219.Nm
220utility appeared in
221.At v7 .
222