This post is a quick ref on the linux touch command. All the examples have been tested on Linux.

This command is used to update the access and modification times of files.

• touch’s syntax

touch [option] file_name(s)
touch file1 file2 file3

• Here some examples:

# touch /tmp/file
# ls -l /tmp/file
rw-r--r-- 1 charlybr charlybr 0 Sep 10 16:13 /tmp/file

• Update access and modification time to current time:

# ls -l /tmp/file
rw-r--r-- 1 charlybr charlybr 0 Sep 10 16:13 /tmp/file
# touch /tmp/file
# ls -l /tmp/file
rw-r--r-- 1 charlybr charlybr 0 Sep 10 16:14 /tmp/file

• Update access and modification time to a specified timestamp ([[CC]YY]MMDDhhmm[.ss] format):

# touch -t 09091842 /tmp/file
# ls -l /tmp/file
-rw-r--r-- 1 charlybr charlybr 0 Sep  9 18:42 /tmp/file

• Update access and modification time to a specified date

# touch -d '9 Sep' /tmp/file
# ls -l /tmp/file
-rw-r--r-- 1 charlybr charlybr 0 Sep  9 00:00 /tmp/file
# touch -d '9 Sep 2008 13:14' /tmp/file
# ls -l /tmp/file
-rw-r--r-- 1 charlybr charlybr 0 Sep  9 13:14 /tmp/file

Links

• touch is part of the Coreutils package
• touch documentation page
• man page on FreeBSD