sfuzz, a mutation file format fuzzer

I thought I might as well publish some code, well here is a little something I have been working on. A simple mutation fuzzer. It just does _dumb_ fuzzing for now but I intend to improve it for structural correctness while fuzzing and smarter fault injections. Not yet completed but It has already shown results, caused many apps to crash with mostly being Invalid reads and 1 Invalid write [dunno if exploitable? will check that out]. Anyway here is the code for the fuzzer. Also, I am thinking towards writing a smart generation fuzzer for structured non binaries. Anyway here is the code...

Source[Linux]:
http://pastebin.com/kVNyKsip

EDIT: A small bug... the randomization depends on the current time. This means to achieve a bit decent randomization, a sleep value of 1s is at least needed.