Change file timestamps. 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.
Syntax
touch [-acfhm] [-r file] [-t [[CC]YY]MMDDhhmm[.SS]] file ...
Options
-a Change the access time of the file. The modification time of the
file is not changed unless the -m flag is also specified.
-c Do not create the file if it does not exist. The touch utility
does not treat this as an error. No error messages are displayed
and the exit value is not affected.
-f Attempt to force the update, even if the file permissions do not
currently permit it.
-h If the file is a symbolic link, change the times of the link
itself rather than the file that the link points to. Note that
-h implies -c and thus will not create any new files.
-m Change the modification time of the file. The access time of the
file is not changed unless the -a flag is also specified.
-r Use the access and modifications times from the specified file
instead of the current time of day.
-t Change the access and modification times to the specified time.
The argument should be in the form `[[CC]YY]MMDDhhmm[.SS]'
where each pair of letters represents the following:
CC The first two digits of the year (the century).
YY The second two digits of the year. If ``YY'' is
specified, but ``CC'' is not, a value for ``YY''
between 69 and 99 results in a ``CC'' value of 19.
Otherwise, a ``CC'' value of 20 is used.
MM The month of the year, from 1 to 12.
DD the day of the month, from 1 to 31.
hh The hour of the day, from 0 to 23.
mm The minute of the hour, from 0 to 59.
SS The second of the minute, from 0 to 61.
If the `CC' and `YY' letter pairs are not specified, the val-
ues default to the current year. If the `SS' letter pair is
not specified, the value defaults to 0.
Example
touch 0512301259 MyFile.txt
Notes
The obsolescent form of touch, where a time format is specified as the
first argument, is supported. When no -r or -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 `MMDDhhmm[YY]'. The `MM', `DD', `hh' and `mm' letter
pairs are treated as their counterparts specified to the -t option. If the `YY'
letter pair is in the range 39 to 99, the year is set to 1939 to 1999, otherwise,
the year is set in the 21st century.
Exits 0 on success, and >0 if an error occurs.
“If you play it safe you stagnate is this league. Maybe we'll bust, but if we hit it, we'll hit it big” - Jimmy Johnson, coach of the Miami Dolphins
Related:
touch man page - Apple.com
chgrp - Change group ownership
chmod - Change access permissions
chown - Change file owner and group
date - Display or change the date
which - Show full path of commands
