Question about portability issues

[Arthur B. Smith]

Greetings netlanders!

    Pardon the extreme cross posting!  We are working on a large
software project (ca. 20+ person-years).  It has been developed thus
far in C to run on a DECstation 3100 running Ultrix (BSD derived)
using X11R3 (but not DECwindows).  It is a multi-process system, with

    It has become apparent that we will need to have this system
running on a Silicon Graphics 4d series box running IRIX (System V
derived), and a scaled down version of this system on some 80386 or
80486 based "PC" running Xenix or some other *ix. These will probably
all be developed in parallel (common source, using #ifdef's and the
like where necessary). 

    Unfortunately, all of us are raw novices at this cross-system
portability issue, and we collectively have very little experience on
non-BSD derived Unixen.

    What I am looking for, therefore, is any wisdom on what is going
to be necessary.  I am looking for any of:

    * How much more time (than just developing under Ultrix) will this
      take? 

    * Should some people develop and others port, or should we all
      learn to write portable code by porting what we write.

    * Any recommendations for a 386/486 box and/or operating system?

    * Any major pitfalls to avoid?  If we can learn from other's
      mistakes, that would be wonderful!

    * Any problems with using BSD sockets?  X Windows?  File system
      issues?  Something else?

    * Any techniques that you have found helpful in doing this type of
      thing?

    Please respond by e-mail to art at dinorah.wustl.edu or
...!uunet!wucs1!dinorah!art (I can't possibly find time to follow ALL
these groups! 8^).  If you are interested in a summary of the
responses, please indicate that, and what newsgroup you would like to
see it in if there are a lot of requests.  I will summarize in one
form or another to all who ask.

    	 Thanks in advance!
    	    -art smith
(art at dinorah.wustl.edu   or   ...!uunet!wucs1!dinorah!art)

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