Next: b2sum invocation, Previous: sum invocation, Up: Summarizing files [Contents][Index]
cksum
: Print and verify file checksumscksum
by default computes a cyclic redundancy check (CRC) checksum
for each given file, or standard input if none are given or for a
file of ‘-’.
cksum also supports the -a,--algorithm option to select the
digest algorithm to use. cksum
is the preferred interface
to these digests, subsuming the other standalone checksumming utilities,
which can be emulated using cksum -a md5 --untagged "$@"
etc.
Synopsis:
cksum [option]… [file]…
cksum
is typically used to ensure that files have not been corrupted,
by comparing the cksum
output for the received files with the
cksum
output for the original files (typically given in the
distribution).
cksum
by default prints the POSIX standard CRC checksum
for each file along with the number of bytes in the file,
and the file name unless no arguments were given.
The same usage and options as the b2sum
command are supported. See b2sum invocation.
In addition cksum
supports the following options.
Compute checksums using the specified digest algorithm.
Supported legacy checksums (which are not supported by --check):
‘sysv’ equivalent tosum -s
‘bsd’ equivalent tosum -r
‘crc’ equivalent tocksum
(the default)
Supported more modern digest algorithms are:
‘md5’ equivalent tomd5sum
‘sha1’ equivalent tosha1sum
‘sha224’ equivalent tosha224sum
‘sha256’ equivalent tosha256sum
‘sha384’ equivalent tosha384sum
‘sha512’ equivalent tosha512sum
‘blake2b’ equivalent tob2sum
‘sm3’ only available throughcksum
Output extra information to stderr, like the checksum implementation being used.
Output using the original Coreutils format used by the other
standalone checksum utilities like md5sum
for example.
This format has the checksum at the start of the line, and may be
more amenable to further processing by other utilities,
especially in combination with the --zero option.
Note this does not identify the digest algorithm used for the checksum.
See md5sum invocation for details of this format.
Next: b2sum invocation, Previous: sum invocation, Up: Summarizing files [Contents][Index]