[fpc-pascal] Porting from Turbo Pascal to FPC

[Tomas Hajny]

On 2020-04-30 10:29, Elmar Haneke wrote:
> Am 29.04.20 um 10:42 schrieb Francisco Glover via fpc-pascal:
>> Overt the years I have developed programs  in Turbo Pascal for student
>> lab use, in which the student can easily send to an attached printer
>> contents of the text or VGA graphics screens. These no longer work on
>> Windows 10.  In shifting to FPC , certain key procedures which worked
>> in Turbo Pascal running on Windows XP no longer work in FPC running on
>> Windows 10. Samples are shown below:
> 
> The Problem depends more on moving from DOS to Windows than movong from
> very old TP to FPC.
> 
> It might be an option to use DOSBox to run that old software.

Indeed, the point of the original poster is not related to FPC versus TP 
but rather porting low-level DOS access to other operating systems - FPC 
would probably allow using these low-level constructs without problems 
for the DOS target (either without changes with the 16-bit msdos target, 
or with rather minor changes with the 32-bit GO32v2 target).

Talking about DOSBox, things like printing may still not work very well 
there, although there seem to be modified versions of DOSBox which may 
have better support for this functionality according to a very quick 
Google search. In any case, it's probably better to bite the bullet and 
rewrite the low-level parts of that old application. The other option 
might be running DOS in a full-featured virtualized environment (e.g. 
VirtualBox).

Tomas