Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!ucsd!ucbvax!SABER.COM!wyant
From: wyant@SABER.COM
Newsgroups: comp.soft-sys.andrew
Subject: Re:  porting atk to VMS ?
Message-ID: <9011071749.AA03496@riposte>
Date: 7 Nov 90 17:49:37 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 20

The dynamic loading is probably not the hard part of porting
to VMS. VMS actually has a callable dynamic loader, in the form
of the 'lib_$find_symbol' library call. This call takes an object file
name and a symbol name. It loads the object file and returns a pointer
to the given symbol (if present).  For an example of layer ATK on top
of an existing dynamic loader look at the Apollo specific code, which
uses the existing Apollo/Domain-OS dynamic loader.

My guess as to what will be hardest to do is asynchronous I/O handling
(read select). Since, last time I looked, VMS didn't provide a select
as part of their C Library, you'll have to dummy up your own (using
event flags I guess). The other problems that you encounter will probably
have to do with terminal IO (setting PTY characteristics), and differences
in signal handling.

I don't think its an entirely crazy idea. Did'nt someone at IBM do a trial
port to OS/2 ? So in theory it is possible to port away from Unix.

-- Geoff Wyant
wyant@saber.com