from the first look it seems that the application tries to use share.exe extensions.

DOSBox provides 127 files by default. Providing 250 is only possible after recompilation.
The problem might be the share thing instead of the files thing, but it's a guess.

Zajec can install another DOS (FreeDOS for example) inside DOSBOX and try again, isn't it?

yes. quite a few dos versions work inside dosbox. I know for sure that msdos 5.0 works quite nicely

I tried FreeDOS inside of Qemu and VMware ─ it is not better. Subiekt claims that it can open only 17 files (I reported this as bug to FreeDOS team)

Qbix wrote:

DOSBox provides 127 files by default. Providing 250 is only possible after recompilation.
The problem might be the share thing instead of the files thing, but it's a guess.

OK, I'll try to compile dosbox myself and will give you info. Just a one question: where I can change this value?

dos_inc.h, #define DOS_FILES 127

There should be some drdos/opendos/caldera dos available (whoever has
the rights currently), maybe try that one as well. It's quite advanced and
compatible to msdos.

wd wrote:

dos_inc.h, #define DOS_FILES 127

I changed this value to 250, compiled dosbox and it works FINE. What about changing this define in main tree? Just to prevent such a problems in future 😀

Btw. I can not run other DOS implementation inside of dosbox because I would have to use disk image. And this is not acceptable for me because other ppl have to have access to files Subiekt is modifing.

Well, I did not say this precisely. There is still first alert about low value of "FILES" but when I click to ignore this, I can continue my work without problems. Before this recompiling Subiekt was just self-closing.

Don't know what dos structures are affected, think the psp field might grow
thus it's better to leave it for games/apps that "don't expect this".
Anyways it's more bad programming of the app if they need that many
open files.

I recall something that the most significant bit on in the psp (so the filenumber) was sometimes uses to detect network files. Something like that is the reason why we set it at 127 (that is the msb cleared)