Date: Wed, 2 Nov 94 02:44:07 JST
From: Stephen Turnbull <turnbull AT shako DOT sk DOT tsukuba DOT ac DOT jp>
To: LIP AT odie DOT ee DOT wits DOT ac DOT za
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu, Dylan AT takoyaki DOT demon DOT co DOT uk,
        (Hot, Shit, Programmer), justin AT qdeck DOT com
Subject: QDLIB200 QDTKT200

[Dylan:  hate to tell you this, but ....]
[Justin:  would you mind passing this to the appropriate quarters for
 official comment?  I would especially like to know if the library at
 least complains and says "you can't run this program with DV/X
 version lower than 2.00" or something like that.]

   From: "Anthony Lipworth" <LIP AT odie DOT ee DOT wits DOT ac DOT za>

   Stephen Turnbull <turnbull AT shako DOT sk DOT tsukuba DOT ac DOT jp> wrote:
   > qddvx102.zip can be
   > eliminated, as AFAIK it has no functionality that is not provided by
   > QDLIB200.ZIP.  QDTKT200.ZIP is docs [& toolkit] for the last.  

To those of you not in the know ("APPLEYARD" for one asked), the "DVX"
stands for DESQview/X which is "QD" = Quarterdeck Office System's
proprietary implementation of an X11R4 server along with a
multitasking OS extension to DOS.  DV/X is to DOS as toast with jam is
to raw sourdough.  QDDVX10x is a set of X11R4 libraries which can be
used to develop or port X windows programs under DJGPP to be run in
conjunction with DV/X; QDLIB200 is a similar library with X11R5
functionality.  Neither can be used to communicate with an X server
without the mediation of a local copy of DV/X.

   The "readme" (I forget the exact filename) mentions that one needs 
   DVX 2 to use these new versions: In your opinion, is there really 
   anything in these updated versions of the DJGPP X libs that would 
   prevent them from being used to create apps to be run under older 
   versions of DVX eg. 1.0x? i.e. could qdlib200 and qdtkt200 be used 
   with DVX 1.0x? I have not tried this yet (no time...).

   Is there a major "internal" difference between DVX 1.0x and 2.x?

   Tony.

I don't know whether the readme is accurate; I haven't tried the libs
with 1.1 or 1.0x.  I imagine that they are accurate, however.  Damn.
This means I'm going to have to put 1.1 and maybe even 1.02 back up
and check them out.
    From the point of view of remote X programs, there are no relevant
internal changes; both DV/X 1.xy and DV/X 2.00 speak fluent X11
protocol over Berkeley sockets.  I believe that the dwm window manager
is ICCCM compliant in all versions.  Unfortunately, from the point of
view of local programs, the answer is quite different.
    Yes, it is highly likely that changes in internals of DV/X could
make it impossible to use the new libraries with old DV/Xes.  DV/X
based X applications are almost standalone, but they do communicate
with any X server, including those on the same (Intel 80[345]86) host,
via Berkeley sockets.  DOS does not provide sockets, whether as shared
memory on a single machine (like teats on a boar hog), nor for
networking.  [I have no idea whether a DV/X socket can communicate
with, say, a WinSOCK on the same machine.  I would guess not; although
you might be able to connect a DV/X socket to a WinSOCK socket on
127.0.0.1 (the loopback IP) if you have a network installed, assuming
the resource contention problem can be solved.]
    AFAIK, QDDVX102 and QDLIB200 do not provide sockets themselves;
they provide entries into the socket routines internal to the DV/X
server.  The internal code for DV/X 2 was completely reworked to be
vastly more efficient and provide more functionality (although the
server is still X11R4 with minor extensions, not X11R5).  Based on the
improvement in performance, obviously the networking code, presumably
including the socket code, was completely revamped.  So the entries in
the libraries are probably different.  Thus the libs could very well
be completely incompatible with earlier DV/Xes.  This would be a
pity....  I am not a Quarterdeck employee (if I were I'd have to act
ashamed of plugging them the way I do :-), so I'm not privy to
implementation details.
    On the other hand, I haven't yet seen any cries of anguish on
comp.os.msdos.desqview from DV/X 1.xy users who can't get Takoyaki XRn
to run, so maybe it's not a problem.  :-)

+-----------------------------------------------------------------------+
|                           Stephen Turnbull                            |
|     University of Tsukuba, Institute of Socio-Economic Planning       |
|          Tennodai 1-chome 1--1, Tsukuba, Ibaraki 305 JAPAN            |
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|                                                                       |
|                Founder and CEO, Skinny Boy Associates                 |
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