🚀 go-pugleaf

> Why is the call to WaitForSomething ifdef'ed out for SYSV in the R4 xdm?
> Is their some fundamental problem with supporting XDMCP on System 5 that
> I should be aware of?

Not really; I didn't spend the time to port it.  SYSV isn't exactly a fun
debugging environment.  I don't envision any real problems except those
with SYSV signals; xdm does some crufty things which may get botched with
unreliable signal handling.  Perhaps someone with experience using SYSV
reliable signals could perform the necessary changes.

> There appears to be no code to perform byte-swapping for XDMCP in the server
> or xdm.

The XDMCP implementation provided with R4 is byte-order independent; it
will work correctly on both big-endian and little-endian machines

> Is there any reason why the execute() function was not used in place of
> execve() in xdm/session.c?

No there isn't -- in fact the execute function was written to be used in
exactly those places, somehow it was never set up correctly (whoops!).

Keith Packard
MIT X Consortium