SUM(1) SUM(1) NAME sum, md5sum, sha1sum - sum and count blocks in a file SYNOPSIS sum [ -5r ] [ file ... ] md5sum [ file ... ] sha1sum [ -2 bits ] [ file ... ] DESCRIPTION By default, sum calculates and prints a 32-bit hexadecimal checksum, a byte count, and the name of each file. The checksum is also a function of the input length. If no files are given, the standard input is summed. Other sum- ming algorithms are available. The options are -r Sum with the algorithm of System V's sum -r and print the length (in 1K blocks) of the input. -5 Sum with System V's default algorithm and print the length (in 512-byte blocks) of the input. Sum is typically used to look for bad spots, to validate a file communicated over some transmission line or as a quick way to determine if two files on different machines might be the same. Md5sum computes the 32 hex digit RSA Data Security, Inc. MD5 Message-Digest Algorithm described in RFC1321. Sha1sum computes the 40 hex digit National Institute of Standards and Technology (NIST) SHA1 secure hash algorithm described in FIPS PUB 180-1, by default. Given the `2' option, it instead computes the bits-bit NIST SHA2 secure hash algorithm described in FIPS PUB 180-2 and prints the hash in hex. Currently supported values of bits are 224, 256, 384, and 512. SOURCE /sys/src/cmd/sum.c /sys/src/cmd/md5sum.c /sys/src/cmd/sha1sum.c SEE ALSO cmp(1), wc(1), sechash(2) Page 1 Plan 9 (printed 7/29/21)