Mr Amit Kale has developed kgdb, a source level debugger for Linux
Kernel. It is used along with gdb to debug Linux Kernel.
URL http://kgdb.linsyssoft.com/

One Day One Command
===================

sum — Compute and Check .

Summary:

`sum’ computes a 16-Bit checksum for each given file(s)/stdin. By
default, it computes checksums using an algorithm compatible with
BSD `sum’ and prints file sizes in units of 1024-byte blocks.

Example:

$ sum file — Print checksum and block counts.

$ sum file1 file2 — Print checksum, block counts and filename.

$ sum -r file — Default. Use BSD sum algorithm (1KB/Block).

$ sum -s file — Use System V sum algorithm (512 bytes/Block).