xref: /freebsd/usr.bin/touch/touch.1 (revision 401c9fda42a465243e0816e882373e14c30c9df1)
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.\" 4. Neither the name of the University nor the names of its contributors
16.\"    may be used to endorse or promote products derived from this software
17.\"    without specific prior written permission.
18.\"
19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29.\" SUCH DAMAGE.
30.\"
31.\"     @(#)touch.1	8.3 (Berkeley) 4/28/95
32.\" $FreeBSD$
33.\"
34.Dd February 4, 2012
35.Dt TOUCH 1
36.Os
37.Sh NAME
38.Nm touch
39.Nd change file access and modification times
40.Sh SYNOPSIS
41.Nm
42.Op Fl A Ar [-][[hh]mm]SS
43.Op Fl achm
44.Op Fl r Ar file
45.Op Fl t Ar [[CC]YY]MMDDhhmm[.SS]
46.Ar
47.Sh DESCRIPTION
48The
49.Nm
50utility sets the modification and access times of files.
51If any file does not exist, it is created with default permissions.
52.Pp
53By default,
54.Nm
55changes both modification and access times.  The
56.Fl a
57and
58.Fl m
59flags may be used to select the access time or the modification time
60individually.
61Selecting both is equivalent to the default.
62By default, the timestamps are set to the current time.
63The
64.Fl t
65flag explicitly specifies a different time, and the
66.Fl r
67flag specifies to set the times those of the specified file.
68The
69.Fl A
70flag adjusts the values by a specified amount.
71.Pp
72The following options are available:
73.Bl -tag -width Ds
74.It Fl A
75Adjust the access and modification time stamps for the file by the
76specified value.
77This flag is intended for use in modifying files with incorrectly set
78time stamps.
79.Pp
80The argument is of the form
81.Dq [-][[hh]mm]SS
82where each pair of letters represents the following:
83.Pp
84.Bl -tag -width Ds -compact -offset indent
85.It Ar -
86Make the adjustment negative: the new time stamp is set to be before
87the old one.
88.It Ar hh
89The number of hours, from 00 to 99.
90.It Ar mm
91The number of minutes, from 00 to 59.
92.It Ar SS
93The number of seconds, from 00 to 59.
94.El
95.Pp
96The
97.Fl A
98flag implies the
99.Fl c
100flag: if any file specified does not exist, it will be silently ignored.
101.It Fl a
102Change the access time of the file.
103The modification time of the file is not changed unless the
104.Fl m
105flag is also specified.
106.It Fl c
107Do not create the file if it does not exist.
108The
109.Nm
110utility does not treat this as an error.
111No error messages are displayed and the exit value is not affected.
112.It Fl h
113If the file is a symbolic link, change the times of the link
114itself rather than the file that the link points to.
115Note that
116.Fl h
117implies
118.Fl c
119and thus will not create any new files.
120.It Fl m
121Change the modification time of the file.
122The access time of the file is not changed unless the
123.Fl a
124flag is also specified.
125.It Fl r
126Use the access and modifications times from the specified file
127instead of the current time of day.
128.It Fl t
129Change the access and modification times to the specified time instead
130of the current time of day.
131The argument is of the form
132.Dq [[CC]YY]MMDDhhmm[.SS]
133where each pair of letters represents the following:
134.Pp
135.Bl -tag -width Ds -compact -offset indent
136.It Ar CC
137The first two digits of the year (the century).
138.It Ar YY
139The second two digits of the year.
140If
141.Dq YY
142is specified, but
143.Dq CC
144is not, a value for
145.Dq YY
146between 69 and 99 results in a
147.Dq CC
148value of 19.
149Otherwise, a
150.Dq CC
151value of 20 is used.
152.It Ar MM
153The month of the year, from 01 to 12.
154.It Ar DD
155the day of the month, from 01 to 31.
156.It Ar hh
157The hour of the day, from 00 to 23.
158.It Ar mm
159The minute of the hour, from 00 to 59.
160.It Ar SS
161The second of the minute, from 00 to 61.
162.El
163.Pp
164If the
165.Dq CC
166and
167.Dq YY
168letter pairs are not specified, the values default to the current
169year.
170If the
171.Dq SS
172letter pair is not specified, the value defaults to 0.
173.El
174.Sh EXIT STATUS
175.Ex -std
176.Sh COMPATIBILITY
177The obsolescent form of
178.Nm ,
179where a time format is specified as the first argument, is supported.
180When no
181.Fl r
182or
183.Fl t
184option is specified, there are at least two arguments, and the first
185argument is a string of digits either eight or ten characters in length,
186the first argument is interpreted as a time specification of the form
187.Dq MMDDhhmm[YY] .
188.Pp
189The
190.Dq MM ,
191.Dq DD ,
192.Dq hh
193and
194.Dq mm
195letter pairs are treated as their counterparts specified to the
196.Fl t
197option.
198If the
199.Dq YY
200letter pair is in the range 39 to 99, the year is set to 1939 to 1999,
201otherwise, the year is set in the 21st century.
202.Sh SEE ALSO
203.Xr utimes 2
204.Sh STANDARDS
205The
206.Nm
207utility is expected to be a superset of the
208.St -p1003.2
209specification.
210.Sh HISTORY
211A
212.Nm
213utility appeared in
214.At v7 .
215