David Griffith wrote: It's not what you asked for but I was curious about "extremely portable". I downloaded the source from github onto a VMS system and unzipped it. I started compiling relevant looking stuff in the common directory using just the C compiler available at hand with no command qualifiers. Attempts to link suggested I needed more and it looked likely that the files in the dumb directory would satisfy the unresolved externals so I compiled those too and linked them in. This made all the unresolveds go away. Having read absolutely no documentation whatsoever and never so much as looked at a Z-machine emulator before, within 17 minutes of starting from scratch, I had an executable which was able to make a more than passable attempt at running several of the files in the test directory. None of the compiles produced any errors or informational messages - there were just two warnings for pointer mismatches due to signed versus unsigned chars in dumb_input.c. I'd say extremely portable is a valid description. It's also extremely easy to build. Still love that sig. Regards, Peter Coghlan.