touch

touch linux command cheatsheet by Thamizhiniyan C S

Introduction

The primary function of the touch command is to modify a file's timestamp. While it is often used to create files, this is not its main purpose.

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Syntax

touch [OPTION]... FILE...

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Important Flags

Flag	Description
-a	change only the access time
-c, --no-create	do not create any files
-d, --date=STRING	parse STRING and use it instead of current time
-f	(ignored)
-h, --no-dereference	affect each symbolic link instead of any referenced file (useful only on systems that can change the timestamps of a symlink)
-m	change only the modification time
-r, --reference=FILE	use this file's times instead of current time
-t STAMP	use [[CC]YY]MMDDhhmm[.ss] instead of current time
--time=WORD	change the specified time: WORD is access, atime, or use: equivalent to -a: WORD is modify or mtime: equivalent to -m
--help	display this help and exit
--version	output version information and exit

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Time Stamp Formats

Syntax: [[CC]YY]MMDDhhmm[.ss]

Format	Description
CC	the first two digits for a year
YY	the last two digits for a year
MM	the month
DD	the day
hh	the hour
mm	the minutes
ss	the seconds

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Examples

Command	Description
touch filename	To create a emtpy file
touch File1_name File2_name File3_name	To create multiple files at the same time. These files will be empty upon creation.
touch test{1..10}	To create ten files with appended numbering
touch test_{a..j}	To create ten files with appended alphabets
touch -a [filename]	To change a file's access time to the current timestamp.
touch -at [timestamp] [filename]	To modify access time explicitly.
touch -am [filename]	To change both modification and access times to the current timestamp.
touch -c fileName	Checks if a file is created; if not, it doesn’t create it.
touch -c -d fileName	Updates both access and modification times.
touch -m [filename]	To change a file's modification time to the current timestamp.
touch -mt [timestamp] [filename]	To set modification time explicitly.
touch -d "17 Mar 2023" fileName	Changes the modification date only.
touch -r [reference file] [file]	To set a file's timestamp based on another file's timestamp.
touch -r second_file_name first_file_name	Uses the timestamp of another file.
touch -t YYMMDDHHMM fileName	Creates a file with a specified time.
touch -t [timestamp] [existing_filename]	To set a specific timestamp for an existing file.
touch -h [filename]	To modify the timestamp of a symbolic link without affecting the referenced file.