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5 Ways to Empty a File on Linux

Like most operations on any Operating System, there are several ways to do basic file manipulation on Linux. Below are 5 different ways to empty a file.

Simple Redirection

Redirection is usually used to output command results to a file.  However, if we redirect “nothing” to a file, we can overwrite it with a blank file. Redirection can be done using a “>” greater-than symbol or a “|” pipe symbol.

# > file.txt
or
# :> file.txt

REDIRECT THE echo command

Use the echo command to redirect null values to a file.

# echo -n > file.txt
  • n do not output the trailing newline.

UsE THE truncate command

Use the truncate command to shrink or expand the size of a file to the size specified by the s option value. Use zero to make the file empty.

# truncate -s 0 file.txt
or
# truncate file.txt --size 0

REDIRECT THE /dev/null device

The null device is usually used for disposing of unwanted output streams of a process or as a empty file for input streams or a redirection operation.

# cat /dev/null > file.txt
or
# cp /dev/null file.txt
cp: overwrite 'file.txt'? y

SCRIPT THE Vim Editor

Vim is a text editor built to make creating and changing any kind of text very efficient. It is included as “vi” in most Linux/Unix systems.

# ex -sc ':%d|x' file.txt
or
# ex -sc ':1,$d|x' file.txt
  • ex : Enter into Ex mode
  • s : Silent; do not display prompts
  • c : Run the given ex command upon startup
  • : : Invoke an ex command
  • % : Choose all the lines
  • d : Delete selected lines
  • x : save and close
  • 2g.txt : input filename