ctypes.sh VS pdd.sh

It's a funny trick, but you could probably also use setjmp and longjmp with ctypes.sh :-)

https://github.com/taviso/ctypes.sh

rundll32.exe is just a way of doing FFI from as a command -- there are few different options on UNIX-likr systems for that. The most obvious is ctypes.sh [0].

There are, though, even more sophisticated options than just FFI, like the Witchcraft Compiler Collection [1], which includes among other things an interactive shell.

[0] https://github.com/taviso/ctypes.sh

[1] https://github.com/endrazine/wcc

github.com/bkw777/dlplus is the part that emulates the drive. It acts like a server listening on a serial port.To test it, you'd need a client, which is normally a TRS-80 Model 100 running TS-DOS, but if you don't have one of those, then github.com/bkw777/pdd.sh is a client implemented in pure bash, which you can run on anything. It's still going to be a bit annoying hardware wise since you still need serial ports and a null-modem cable. Two generic usb-serial adapters and a null-model adapter works, as long as the cable includes the rts/cts and dsr/dtr lines, either real or at least looped-back at the connectors.