[apple/file_cmds.git] / touch / touch.1

.\"	$NetBSD: touch.1,v 1.13 1998/01/20 21:18:25 mycroft Exp $
.\"
.\" Copyright (c) 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the Institute of Electrical and Electronics Engineers, Inc.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)touch.1	8.3 (Berkeley) 4/28/95
.\"
.Dd April 28, 1995
.Dt TOUCH 1
.Os
.Sh NAME
.Nm touch
.Nd change file access and modification times
.Sh SYNOPSIS
.Nm
.Op Fl acfhm
.Op Fl r Ar file
.Op Fl t Ar [[CC]YY]MMDDhhmm[.SS]
.Ar file ...
.Sh DESCRIPTION
The
.Nm
utility sets the modification and access times of files to the
current time of day.
If the file doesn't exist, it is created with default permissions.
.Pp
The following options are available:
.Bl -tag -width Ds
.It Fl a
Change the access time of the file.
The modification time of the file is not changed unless the
.Fl m
flag is also specified.
.It Fl c
Do not create the file if it does not exist.
The
.Nm
utility does not treat this as an error.
No error messages are displayed and the exit value is not affected.
.It Fl f
Attempt to force the update, even if the file permissions do not
currently permit it.
.It Fl h
If
.Ar file
is a symbolic link, access and/or modification time of the link is changed.
This option implies
.Fl c .
.It Fl m
Change the modification time of the file.
The access time of the file is not changed unless the
.Fl a
flag is also specified.
.It Fl r
Use the access and modifications times from the specified file
instead of the current time of day.
.It Fl t
Change the access and modification times to the specified time.
The argument should be in the form
.Dq [[CC]YY]MMDDhhmm[.SS]
where each pair of letters represents the following:
.Pp
.Bl -tag -width Ds -compact -offset indent
.It Ar CC
The first two digits of the year (the century).
.It Ar YY
The second two digits of the year.
If
.Dq YY
is specified, but
.Dq CC
is not, a value for
.Dq YY
between 69 and 99 results in a
.Dq CC
value of 19.
Otherwise, a
.Dq CC
value of 20 is used.
.It Ar MM
The month of the year, from 1 to 12.
.It Ar DD
The day of the month, from 1 to 31.
.It Ar hh
The hour of the day, from 0 to 23.
.It Ar mm
The minute of the hour, from 0 to 59.
.It Ar SS
The second of the minute, from 0 to 61.
.El
.Pp
If the
.Dq CC
and
.Dq YY
letter pairs are not specified, the values default to the current
year.
If the
.Dq SS
letter pair is not specified, the value defaults to 0.
.El
.Pp
The
.Nm
utility exits 0 on success, and >0 if an error occurs.
.Sh SEE ALSO
.Xr utimes 2
.Sh COMPATIBILITY
The obsolescent form of
.Nm "" ,
where a time format is specified as the first argument, is supported.
When no
.Fl r
or
.Fl t
option is specified, there are at least two arguments, and the first
argument is a string of digits either eight or ten characters in length,
the first argument is interpreted as a time specification of the form
.Dq MMDDhhmm[YY] .
.Pp
The
.Dq MM ,
.Dq DD ,
.Dq hh
and
.Dq mm
letter pairs are treated as their counterparts specified to the
.Fl t
option.
If the
.Dq YY
letter pair is in the range 69 to 99, the year is set to 1969 to 1999,
otherwise, the year is set in the 21st century.
.Sh STANDARDS
The
.Nm
utility is expected to be a superset of the
.St -p1003.2
specification.
.Sh HISTORY
A
.Nm
utility appeared in
.At v7 .
.Sh BUGS
A symbolic link can't be a reference file of access and/or modification time.
Commit	Line	Data
44a7a5ab A	1	.\" $NetBSD: touch.1,v 1.13 1998/01/20 21:18:25 mycroft 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
	52	The
	53	.Nm
	54	utility sets the modification and access times of files to the
	55	current time of day.
	56	If the file doesn't exist, it is created with default permissions.
	57	.Pp
	58	The following options are available:
	59	.Bl -tag -width Ds
	60	.It Fl a
	61	Change the access time of the file.
	62	The modification time of the file is not changed unless the
	63	.Fl m
	64	flag is also specified.
65	.It Fl c
66	Do not create the file if it does not exist.
67	The
68	.Nm
69	utility does not treat this as an error.
70	No error messages are displayed and the exit value is not affected.
71	.It Fl f
72	Attempt to force the update, even if the file permissions do not
73	currently permit it.
74	.It Fl h
75	If
76	.Ar file
77	is a symbolic link, access and/or modification time of the link is changed.
78	This option implies
79	.Fl c .
80	.It Fl m
81	Change the modification time of the file.
82	The access time of the file is not changed unless the
83	.Fl a
84	flag is also specified.
85	.It Fl r
86	Use the access and modifications times from the specified file
87	instead of the current time of day.
88	.It Fl t
89	Change the access and modification times to the specified time.
90	The argument should be in the form
91	.Dq [[CC]YY]MMDDhhmm[.SS]
92	where each pair of letters represents the following:
93	.Pp
94	.Bl -tag -width Ds -compact -offset indent
95	.It Ar CC
96	The first two digits of the year (the century).
97	.It Ar YY
98	The second two digits of the year.
99	If
100	.Dq YY
101	is specified, but
102	.Dq CC
103	is not, a value for
104	.Dq YY
105	between 69 and 99 results in a
106	.Dq CC
107	value of 19.
108	Otherwise, a
109	.Dq CC
110	value of 20 is used.
111	.It Ar MM
112	The month of the year, from 1 to 12.
113	.It Ar DD
114	The day of the month, from 1 to 31.
115	.It Ar hh
116	The hour of the day, from 0 to 23.
117	.It Ar mm
118	The minute of the hour, from 0 to 59.
119	.It Ar SS
120	The second of the minute, from 0 to 61.
121	.El
122	.Pp
123	If the
124	.Dq CC
125	and
126	.Dq YY
127	letter pairs are not specified, the values default to the current
128	year.
129	If the
130	.Dq SS
131	letter pair is not specified, the value defaults to 0.
132	.El
133	.Pp
134	The
135	.Nm
136	utility exits 0 on success, and >0 if an error occurs.
137	.Sh SEE ALSO
138	.Xr utimes 2
139	.Sh COMPATIBILITY
140	The obsolescent form of
141	.Nm "" ,
142	where a time format is specified as the first argument, is supported.
143	When no
144	.Fl r
145	or
146	.Fl t
147	option is specified, there are at least two arguments, and the first
148	argument is a string of digits either eight or ten characters in length,
149	the first argument is interpreted as a time specification of the form
150	.Dq MMDDhhmm[YY] .
151	.Pp
152	The
153	.Dq MM ,
154	.Dq DD ,
155	.Dq hh
156	and
157	.Dq mm
158	letter pairs are treated as their counterparts specified to the
159	.Fl t
160	option.
161	If the
162	.Dq YY
163	letter pair is in the range 69 to 99, the year is set to 1969 to 1999,
164	otherwise, the year is set in the 21st century.
165	.Sh STANDARDS
166	The
167	.Nm
168	utility is expected to be a superset of the
169	.St -p1003.2
170	specification.
171	.Sh HISTORY
172	A
173	.Nm
174	utility appeared in
175	.At v7 .
176	.Sh BUGS
177	A symbolic link can't be a reference file of access and/or modification time.