>You might start simple - if you're interested - and don't tell anyone <g> - you might be able to locate an old xBase engine - and crack it - just to see what it's guts look like!
Well, as you said an "old" xBase engine... In the 80's I have once to dissasemble dBase II to fix a little problem it had to be used on a multiuser environment: it never closed the file handles it opened.
Of course, once you USEd a table, nobody else could USE it from other point (shared access wasn't existed at this time), but the real problem was that even once you USEd another table (there was just a single work area to work with), the internal file handle was not released.
I have to confess that the code was quite sloppy. But I wasn't in a position to start working on MartinBase III at the time, so I simply patched it and reassembled. I could look for the code (Z80 assembler) if you want, although I'm not sure I still have it around.
Cheers,