$ curl cheat.sh/
# sha1sum
# Calculate SHA1 cryptographic checksums.
# More information: <https://www.gnu.org/software/coreutils/sha1sum>.

# Calculate the SHA1 checksum for a file:
sha1sum path/to/file

# Calculate SHA1 checksums for multiple 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

# Read a file of SHA1 sums 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 for files for which verification fails, ignoring missing files:
sha1sum --ignore-missing --check --quiet path/to/file.sha1

$
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