From: pderbysh AT chat DOT carleton DOT ca (Paul Derbyshire)
Newsgroups: comp.os.msdos.djgpp
Subject: DJGPP 1.x programs don't work if you get 2.0!
Date: 25 Feb 1997 02:42:27 GMT
Organization: Carleton University, Ottawa, Canada
Lines: 37
Message-ID: <5etjij$ir1@bertrand.ccs.carleton.ca>
NNTP-Posting-Host: wabakimi.carleton.ca
NNTP-Posting-User: pderbysh
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp


I just discovered today that when DJGPP 2.0 is installed, programs written
with DJGPP 1.x you have on your system stop working. Specifically, I often
work with graphics programs, and sometimes these crash or exit abnormally
with the screen lleft in graphics mode. To get a dos prompt back without
painstaking rebooting and laborious startup, I wrote a program called
'resetgr', in DJGPP 1.11, that simply calls int 10h(I think) and sets text
80x25x16 mode, restoring the DOS screen.
Now that I have DJGPP 2, resetgr no longer works, generating the error
"cannot exec GO32". This is obviously a misleading error message since
GO32 (v1) is still on my computer. (I left it in the old D:\DJGPP area
where V1 resided specifically so I could still run V1 programs!) The only
thing I can figure is that removing all the autoexec.bat lines DJGPP 1
needed and replacing them with SET DJGPP=C:\DJGPP\DJGPP.ENV somehow
invalidates anything from 1.x. It's like someone in the djgpp design
department wants to be sure that each time they make a new version of
djgpp, everyone has to edit and recompile all their old projects! Which
seems ludicrous. After all, this would mean that no end user could run
both a 1.x-compiled program and a 2.0 compiled program on the same system,
which is absurd when they are written for the same OS. Since I doubt
anyone would have made it that way, it must be that the 2.0 *development
environment* is incompatible with running 1.x programs. (I shall see if
booting my machine *sans* SET DJGPP=C:\DJGPP\DJGPP.ENV will cause resetgr
to work again.)
(If anyone is wondering, the GO32 v1 is complletely intact. I didn't
replace it with a renamed copy of GO32-v2 (should I have?) nor did I
dellete it or move it from the old D:\DJGPP\BIN directory.)




   .*.  "Clouds are not spheres, mountains are not cones, coastlines are not
-()  <  circles, and bark is not smooth, nor does lightning travel in a
   `*'  straight line."     ------------------------------------------------
        -- B. Mandelbrot   | Paul Derbyshire (PGD) ao950 AT freenet DOT carleton DOT ca
______________________ ____|                       pderbysh AT chat DOT carleton DOT ca
 A quiet kind of guy  | I'm on the Web at: http://chat.carleton.ca/~pderbysh