Cksum

Cksum is a Unix command that computes a checksum and byte count for a file or data stream, reporting a 32-bit cyclic redundancy check value that can be compared against a previously recorded value to confirm a file arrived intact, for example after a transfer over an unreliable connection. Its algorithm is based on the Ethernet standard frame check, using the generator polynomial 0x04C11DB7 and appending the message length in little-endian form before computing the check value. Cksum is standardized under POSIX and is available on Unix-like systems including Linux, the BSD family, macOS and Solaris, commonly through GNU Coreutils. Because a CRC-32 checksum offers no cryptographic security, cksum can catch accidental corruption but cannot be relied on to detect deliberate tampering, since an attacker can construct a modified file with the same checksum value. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/