thanks all for the input, really i already have the byte reversing done, and i dont think reading the whole file in reverse will give me the output i desired :p , but i already have that dealt with anyway, i was just trying to figure out how i could byte reverse it in memory (without having to write it to disk) and only write to disk when needed. some of the tests i did yesterday was trivial, i will post code later on hopefully, if i can get around to it :)