How to use the command cksum (with examples)

The cksum command is used to calculate CRC checksums and byte counts of a file. It helps in verifying the integrity of a file by generating a unique checksum value based on the file’s content. This checksum can be compared with the original checksum to ensure that the file has not been modified or corrupted.

Use case 1: Display a 32-bit checksum, size in bytes, and filename

Code:

cksum path/to/file

Motivation: This use case is useful when you want to quickly check the integrity of a file and ensure it has not been changed or corrupted. By displaying the checksum, size in bytes, and filename, you can compare it with the original values to identify any discrepancies.

Explanation:

• cksum: The command itself.
• path/to/file: The path to the file for which you want to calculate the checksum.

Example output:

3193962756 1024 path/to/file

In this example, the checksum value is 3193962756, the size of the file is 1024 bytes, and the filename is path/to/file. You can use this information to compare with the original values to verify the file’s integrity.

Conclusion:

The cksum command is a handy tool for calculating CRC checksums and byte counts of files. By using it, you can quickly verify the integrity of a file and detect any possible modifications or corruptions.