[Suggestion] Making the D: drive accessible from outside of DosBox Pure

[Ric-82]

RetroArch's save system requires that changes made to the C: and D: drives be saved in files with the .sav extension, which are not browsable.

I swear that in previous versions of the DosBox Pure core, it was possible to load an external VHD as the D: drive (rather than using the standard D: drive created by the core). I used this method to install Windows games in the DosBox D: folder, then load the VHD into Windows 11 and copy the entire game installation folder, either to create a ready-to-use DOSZ file or just to back up game save files, etc.

But now (maybe I'm doing something wrong or the core has been updated), if I load the VHD via the core menu, Windows 9x doesn't see it. The D: drive is still the one created by the core, not my VHD.

Am I doing something wrong, or has the core actually been modified and it's no longer possible to use an external VHD as the D: drive?

In this case, may I suggest implementing a method to make the data stored in DosBox's D: drive usable by the host system?

[emxd]

There has been an issue with loading drives of size over 2GB (https://github.com/schellingb/dosbox-pure/issues/647). Originally it was only present on the GHA builds, but now it's also present in preview3. If your drive is of size bigger than 2GB, try using the preview2 version.

[Ric-82]

Yes, apparently the problem is that my VHD exceeds 2GB (although this wasn't a problem with the previous version of the core). I created a 2GB VHD, and now it's seen correctly. I hope future versions of DosBox will remove this limit and perhaps allow the use of dynamic VHDs. Alternatively (but I don't know how technically feasible this is), it would be even more convenient and straightforward if the D: drive created by DosBox Pure were a sort of shared directory between the host and client systems.

Thanks for your help.

[Ric-82]

I’m sorry to report that after updating to DOSBox Pure 1.0 Preview 4, I can no longer load my 2 GB VHD.

When I try to load it, RetroArch shows an error message: "unable to open CD-ROM image file:" followed by the path where the VHD is located. Other media in that same path are read correctly.

The problem seems to be related to the size of the VHD, but not only that. I created another one slightly below 2 GB (1999 MB), and that one is read correctly. However, if I start the core pointing to the VHD as the content to load, I see the message "D: Will be based on the loaded .IMG file", but once inside the operating system the D: drive is not my VHD — instead it shows up as an empty CD drive.