Bashtouch Command - Change File Timestamps

Using thetouch Command

Thetouch command is used to change file timestamps or create an empty file if it doesn't exist.

It's often used to create placeholder files or update timestamps for build systems.

Basic Usage

To update the access and modification times of a file, usetouch filename:

touch file.txt

Options

Thetouch command has options to change how it works:

• -a - Update only when the file was last read
• -m - Update only when the file was last changed
• -t - Set the timestamp to a specific time
• -c - Do not create any files

-a Option: Change Access Time

The-a option lets you update the access time of a file.

touch -a file.txt

-m Option: Change Modification Time

The-m option lets you update only the modification time of a file.

ls -l-rw-r--r-- 1 user 197609 208 Apr  9 06:24 my_file.txttouch -m my_file.txtls -l-rw-r--r-- 1 user 197609 208 Apr  9 08:25 my_file.txt

-t Option: Set Specific Timestamp

The-t option allows you to set the timestamp to a specific time.

ls -l-rw-r--r-- 1 user 197609 208 Apr  9 06:24 my_file.txttouch -t 202501010000 my_file.txtls -l-rw-r--r-- 1 user 197609 208 Jan  1 00:00 my_file.txt

-c Option: Do Not Create Files

The-c option tellstouch not to create any files if they do not exist.

This is useful when you want to update timestamps without accidentally creating new files.

touch -c non_existent_file.txt

Usingtouch with Wildcards

Wildcards allow you to update timestamps on multiple files at once.

For example,touch *.txt will update the timestamps of all text files in the directory.

touch *.txt