[NAME] sha1sum \- compute and check SHA1 message digest [DESCRIPTION] .\" Add any additional description here [BUGS] Do not use the SHA-1 algorithm for security related purposes. Instead, use an SHA\-2 algorithm, implemented in the programs sha224sum(1), sha256sum(1), sha384sum(1), sha512sum(1), or the BLAKE2 algorithm, implemented in b2sum(1) [SEE ALSO] cksum(1)