Is there safe way to detect is esxDos present on machine or not?

I'm talking about multiloaders when you have one code for several versions of demo/application.

For example, esxDos present - read via it from folder, if not - trying detect TRDOS - read from floppy(in success way) or tape.

It's probably better to build a dedicated esxDOS target. If you use the .RUN command, you can build it as an app.

But to answer your question, hack the error handler and then issue a hook code. If you get an expected response it's esxDOS, if not, it's not.

I'm talking about multiloaders when you have one code for several versions of demo/application.

For example, esxDos present - read via it from folder, if not - trying detect TRDOS - read from floppy(in success way) or tape.