This is an implementation of the C and POSIX standard library for
v7 Unix on the PDP-11.  If most of this is ever finished, I might
tackle targeting other platforms as well.

You can compile the library using either cc or an ISO C compiler.
You can't compile it using C23, unless the compiler supports
old-style function definitions as an extension.  You can use the
library with cc or with an ISO C compiler, independent of which
was used to compile the library.

Ideas for the far future:

 - The extended execution character set could be UTF-8.

 - Threads could be implemented in user space, similar to Plan 9's
   libthread.

 - Asynchronous i/o could be handled by child processes
   communicating to the main process with pipes.  Poll could
   read from a completion pipe.