sha1sum is a computer program that calculates and verifies SHA-1 hashes. It is commonly used to verify the integrity of files. It (or a variant) is installed by default on most Linux distributions.

What is sha1sum used for?

What is the sha1sum command in UNIX? The sha1sum command computes the SHA-1 message digest of a file. This allows it be compared to a published message digest to check whether the file is unmodified from the original. As such the sha1sum command can be used to attempt to verify the integrity of a file.

How do I run a checksum in Linux?

To run a checksum on a file is simple. Just evoke md5sum followed by the name of the file. Here we generated a checksum of a text file containing all 185 lines of the short story Harrison Bergeron by Kurt Vonnegut. If we edit the file and change one character, the checksum will change.