Ah... Concurrent DOS...
IBM did actually use DR Concurrent DOS 286 - but in their 4680 Point-of-sale (described often as a real P.O.S. by those of us who used it) OS.
IBM did actually use DR Concurrent DOS 286 - but in their 4680 Point-of-sale (described often as a real P.O.S. by those of us who used it) OS.