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6.3 cksum: Print CRC checksum and byte counts

cksum computes a cyclic redundancy check (CRC) checksum for each given file, or standard input if none are given or for a file of ‘-’. Synopsis:

cksum [option]… [file]…

cksum prints the CRC checksum for each file along with the number of bytes in the file, and the file name unless no arguments were given.

cksum is typically used to ensure that files transferred by unreliable means (e.g., netnews) 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).

The CRC algorithm is specified by the POSIX standard. It is not compatible with the BSD or System V sum algorithms (see the previous section); it is more robust.

The only options are --help and --version. See Common options.

An exit status of zero indicates success, and a nonzero value indicates failure.