touch (Create File)
Using the touch command, you can create a new file. You can also use the touch command to change the time stamp of the existing file.
Creating a new file
Simply run the command with a file path with a new file name at the end of the path. For example, to create a new file named new_file_a under your working directory, run the command below.
touch new_file_a
Change the timestamp of an existing file or directory
We'll explain how to change the timestamp of an existing file or directory using the two files like shown below.
ls -l
-rw-rw-r-- 1 ubuntu ubuntu 0 Oct 11 2018 reference.txt
-rw-rw-r-- 1 ubuntu ubuntu 0 Dec 29 04:57 sample.txt
-d option : specify date and time
To change the timestamp of the sample.txt to "2021-11-12 06:00", run the command below.
touch -d "2021-11-12 06:00" sample.txt
You can see the timestamp changed below.
ls -l
-rw-rw-r-- 1 ubuntu ubuntu 0 Oct 11 2018 reference.txt
-rw-rw-r-- 1 ubuntu ubuntu 0 Nov 12 2021 sample.txt
-r (--reference) option : apply another file's timestamp
To change the timestamp of sample.txt to the same timestamp as reference.txt has, run the command below.
touch -r reference.txt sample.txt
You can see that the timestamp changed as shown below.
ls -l
-rw-rw-r-- 1 ubuntu ubuntu 0 Oct 11 2018 reference.txt
-rw-rw-r-- 1 ubuntu ubuntu 0 Oct 11 2018 sample.txt
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