@oblomov @mcSlibinas @calcifer I didn't get it until you mentioned DOS.I've used PC-DOS/MS-DOS some, all the way back to August 12, 1981, the day the IBM PC was introduced, and my boss bought one that day.But the vast majority of my experience is with DEC operating systems, and UNIX and UNIX-like systems (including Linux).PC-DOS and MS-DOS aren't even the operating systems that first come to my mind when I just see "DOS". I'm more likely to think of Apple DOS, or even IBM mainframe DOS.