5 Quick Linux Commands to Empty a File Instantly

This guide shows how to clear the contents of a file in Linux using five straightforward command‑line methods.

1. Redirect to null to empty a file

# > access.log

Redirecting nothing (the null object) to the file overwrites it with no data.

2. Use the built‑in true command

# : > access.log
OR
# true > access.log

The colon (:) is a shell built‑in equivalent to the true command; redirecting its output clears the file.

3. Use cat, cp, or dd with /dev/null

# cat /dev/null > access.log
# cp /dev/null access.log
# dd if=/dev/null of=access.log

The special /dev/null device discards any input, and redirecting its output to a file empties the file.

4. Use echo to write an empty string

# echo "" > access.log
OR
# echo > access.log
# echo -n "" > access.log

Echoing an empty string (or using the -n flag to suppress the newline) overwrites the file with nothing.

5. Use truncate to set file size to zero

# truncate -s 0 access.log

The truncate command reduces the file size to the specified length; using -s 0 clears the file completely.