tldr/pages/common/sha1sum.md

sha1sum

Calculate SHA1 cryptographic checksums. More information: https://www.gnu.org/software/coreutils/manual/html_node/sha1sum-invocation.html.

• Calculate the SHA1 checksum for one or more files:

sha1sum {{path/to/file1 path/to/file2 ...}}

• Calculate and save the list of SHA1 checksums to a file:

sha1sum {{path/to/file1 path/to/file2 ...}} > {{path/to/file.sha1}}

• Calculate a SHA1 checksum from stdin:

{{command}} | sha1sum

• Read a file of SHA1 checksums and filenames and verify all files have matching checksums:

sha1sum --check {{path/to/file.sha1}}

• Only show a message for missing files or when verification fails:

sha1sum --check --quiet {{path/to/file.sha1}}

• Only show a message when verification fails, ignoring missing files:

sha1sum --ignore-missing --check --quiet {{path/to/file.sha1}}

• Check a known SHA1 checksum of a file:

echo {{known_sha1_checksum_of_the_file}} {{path/to/file}} | sha1sum --check