You could mount a DSK file (even FAT12) with OSFMount and there you have your folder. Use the DSK image in OpenMSX. Or isn't this what you meant?
What about implementing a virtual HDD interface/"cartridge" for this? The ROM in the cartridge could contain DOS2 + FAT16 support. DOS2 file-level routines can be routed directly to host OS disk routines, low-level disk routines can be stubbed. Then you do not need to work around or even bother with the peculiarities of existing HDD interfaces.
openmsx -ext dirashdd ~/msx/my_msx_hdd
OMG! That is the most qualified disqualification of a proposal I've ever read!
Hahah, it was especially for you! IRC?
'the most qualified disqualification'
IMO this would be one of the most useful features for developers. Sharing files with the PC (the development machine) is a pain. Using folder as FDD is also a pain because slow access and size limit (fragmentation of your files and versions of these in many disks).
Issue opened, it should be really great for developers since the file sharing with PC should be fast: graphics, music, code... everything in realtime.
I stick to what I use, mount the dsk image on the pc with OSFMount and share the image with OpenMSX. Then I can work in a folder and see results in OpenMSX directly.
DarkSchneider: if the slow access is bothering you, you probably don't have the "fullspeedwhenloading" setting enabled? See http://openmsx.org/manual/commands.html#fullspeedwhenloading
Size limit remains, but why is that a problem? You do the development in your own git repo (or whatever you like) and your build-script will output a disk image or file-structure that can be used as disk as if it's ready for a real MSX and then you start openMSX with that disk.... You don't need *all* your dev files in that folder for openMSX, only the ones you need to run on the MSX itself, of course.
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