cksum

Additional Notes

cksum prints a CRC checksum and byte count for files or standard input. It is useful for simple corruption checks and compatibility with POSIX checksum workflows.

For cryptographic integrity, use stronger tools such as sha256sum.

Syntax

cksum [file...]

Parameters

• file: File to checksum. If omitted, standard input is used.
• options: Some implementations support algorithm options, help, and version flags.

Examples

cksum file.txt

Print checksum, byte count, and filename.

echo "hello" | cksum

Checksum standard input.

cksum *.iso

Checksum multiple files.

Practical Notes

• CRC checksums are good for accidental corruption, not security.
• Use sha256sum when verifying downloads from a trusted published hash.
• Output format is usually checksum, byte count, then filename.