> All I'm trying to do is read data from a file byte by byte
 > and through it up on screen as pixels. Simple enough, right?
 > Wrong! The first 2 or 3 thousand bytes go fine but then all
 > other bytes are the same when I know that this not the case.
 > I know I'm not hitting the end of the file because its a 40k
 > file and I'm only pulling out 100x100 i.e. 10000 bytes!!!!!

Unfortunately you aren't specific, so it's stab-in-the-dark time, with a
1:20 chance against getting anywhere near right.

Are you opening the file in binary mode? 

What is the value of the byte you're reading (0xff?)?

Post some code which shows how you're reading it.

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