[fpc-pascal] What is the lowest MS-DOS version supported by FPC?

[Tomas Hajny]

On Sat, May 15, 2010 22:48, "Vinzent Höfler" wrote:
> Bihar Anwar <bihar_anwar at rocketmail.com>
>
>> I've tried googling and searching FPC mailing list for information about
>> this one, but I found nothing.
>> I just found in  http://www.delorie.com/djgpp/v2faq/faq3_1.html  that
>> DJGPP  requires MS-DOS version 3.1 or later.
>>
>> Would someone here tell me exactly about lowest MS-DOS version supported
>> by FPC?
>
> 3.1, I'm pretty sure. AFAIK it doesn't use any specific DOS 5.x+ calls
> except perhaps for checking for existence of DOS 7.x (Win95) LFN
> functions. And DOS 4.x was close to non-existent anyway.

In general, FPC compiled programs (and the compiler itself with some
limitations) should hopefully work correctly under DOS 3.1+ as specified
for DJGPP. Some functionality would not work properly without having at
least MS DOS 3.3+ (increasing of default count of file handles used in
unit system, checking of country information used in SysUtils). However, I
don't think that anyone tried it with anything older than MS-DOS 5.0
recently. If you really need to use an even older version (why?) and if
you encounter difficulties with FPC compiled programs running under such
an old version, let me know, I may try to have a look at it (I'm not
completely sure if I still have access to anything older than MS-DOS 4.01
though).

Note that requirements are different for building RTL and packages for the
GO32v2 target (rather than just using compiled units from a release or a
snapshot). In particular, support for long file names (as available in MS
DOS v7.x or also provided by some TSR utilities) is necessary for using
FPC makefiles to build FPC from provided source files.

Tomas