Sharedmemory

MJP is just my initials. It is a way for my to search for bugs that are mine. This one should have been removed. Before doing it the right way and using fstat to get file size I was just supplying a non NULL value for the mmap size arg. Which worked and let me get on with other things. I knew this was the wrong way to do it so I marked it as a BUG.

  As for the MAP_FAILED define. I will fix this when i get some time. I also like using these defines if I know about them. It makes the code more clear.