Oh, I see. That's useful.
Okay, my next question is kind of hard to describe...basically, I want to find all blocks of data in a file that are composed of a single specified character and have a specified minimum length. (Say, all blocks of character 0x20 that are at least 12 bytes long.) BUT, said blocks a) shouldn't cross certain boundaries (say, they shouldn't overlap between groups of 1000 bytes) and b) shouldn't be taken into account if they are part of a reserved block marked with a certain keyword (say, the ASCII characters "U S E D" followed by the block length). I don't really even know where to start on this...