6 Summarizing files

These commands generate just a few numbers representing entire contents of files.

• wc invocation: Print newline, word, and byte counts.
• sum invocation: Print checksum and block counts.
• cksum invocation: Print CRC checksum and byte counts.
• md5sum invocation: Print or check MD5 digests.
• sha1sum invocation: Print or check SHA-1 digests.
• sha2 utilities: Print or check SHA-2 digests.