The touch command is a standard command available on Unix/Linux systems. It can be used to create new, empty files or change the timestamp on existing files. If there is an existing file named
test.txt created on
January 22, 2016 at 10:13 PM, i.e. 22:13 in the
24-hour time format,
aka "military time", I can change the date to Decembe 25, 2015 and the time
to 5:13 PM by using the command shown below.
$ touch -t 201512251713 test.txt $ ls -l test.txt -rw-rw-r-- 1 joe joe 0 Dec 25 17:13 test.txt
The -t option indicates that I wish to change the time stamp.
It is followed by the date and time in the format YYYYMMDDHHMM where YYYY
represents the year, MM the month, DD the day, HH the hour and MM represents
minutes.
Using the --date argument to the command, you can even specify
a time as YYYY-MM-DD HH:MM. Note: use the
--time-style=long-iso or --time-style=full-iso
options for the ls -l command to show the full timestamp.
$ touch --date="2013-01-25 09:00" example.txt $ ls -l --time-style=long-iso example.txt -rw-rw-r-- 1 joe joe 0 2013-01-25 09:00 example.txt
With the --date option, you can even specify a date in a format
such as "next Friday" or "last Friday". A date string may contain items
indicating calendar date, time of day, time zone, day of week, relative
time, relative date, and numbers. An empty string indicates the beginning of
the day.
E.g., suppose, today is Saturday January 23, but I want to create two new files, one with a date of the prior Friday and one with a date of next Friday. I could use the commands shown below.
$ touch --date="last Friday" oldsample.txt $ touch --date="next Friday" newsample.txt $ ls -l *sample.txt -rw-rw-r-- 1 joe joe 0 Jan 29 2016 newsample.txt -rw-rw-r-- 1 joe joe 0 Jan 22 00:00 oldsample.txt
You can also specify the hours, minutes, and seconds using such a format,
e.g., suppose I already have the file newsample.txt, but want to
change the date and time for the existing file to be this coming Sunday at
11:00 PM. I could use the touch command below.
$ touch --date="Sunday 23:11:05" newsample.txt $ ls -l --time-style="long-iso" newsample.txt -rw-rw-r-- 1 joe joe 0 2016-01-24 23:11 newsample.txt $ ls -l --time-style="full-iso" newsample.txt -rw-rw-r-- 1 joe joe 0 2016-01-24 23:11:05.000000000 +0000 newsample.txt
You can even specify the time down to fractions of a section by putting a period after the seconds value, which appears as HH:MM:SS. E.g.:
$ touch --date="Sunday 23:11:05.01234" newsample.txt $ ls -l --time-style="full-iso" newsample.txt -rw-rw-r-- 1 joe joe 0 2016-01-24 23:11:05.012340000 +0000 newsample.txt
touch
file{n1..n2} where file is the first
part of the file name, n1 is the starting number you wish to add
to the end of the file name, and n2 is the ending number to be
appended to the file name. The touch command will then
create ten files starting with file1 through file10.
$ ls
index.html
$ touch file{1..10}.html
$ ls
file10.html file2.html file4.html file6.html file8.html index.html
file1.html file3.html file5.html file7.html file9.html
