pcmos386v501

of multitasking DOS extensions and replacements: Concurrent DOS 386, DESQview, DESQview/X, PC-MOS 386, TSX-32, and others. Most aimed at multiuser stuff because 386DX kit was expensive. (PC-MOS is FOSS now. https://github.com/roelandjansen/pcmos386v501 ) This drove the market towards the 386. It could do more, even just for DOS and DOS users. I made a good living optimising the memory management of DOS PCs. Once it was established, the much cheaper 386SX came along and made 386 PCs cheap. The tech and the software and the skills were already there. But OS/2 1.x couldn't do any of it. It could barely run DOS at all. If you were a DOS user OS/2 gave you nothing worth having. NT was a hit by aiming at the PCs of the near future. That's what OS/2 should have been targeted at as well. Then gradually, incrementally, Windows 3 took over because it worked on XTs and ATs but on 386s it gave you DOS multitasking and copy-and-paste between DOS apps. It gave you the good stuff you got from DESQview. AND you got new apps. OS/2 1.x was gradual developing. It got a GUI after 1 version. It got a decent GUI next. Then it got smaller and faster. NT was incremental too. 3.1 worked but was huge. 3.5 got VFAT and was smaller and faster with better networking. 3.51 got smaller and faster and stabler and started ditching the OS/2 legacy stuff. The point being, OS/2 1.0 should have gone up against DESQview and Concurrent DOS as a DOS multitasker for rich power users, then OS/2 1.1 against Windows 2, then OS/2 1.3 would have taken the place of Windows 3.

could draw graphs. The snag was that CDOS386 was not a DOS; it was a descendant of Concurrent CP/M. It ran DOS apps but could not use DOS drivers – it needed its own. So adding hardware was not a trivial exercise. Kit had to be chosen from short hardware compatibility list (and was therefore expensive) and drivers supplied as object files relinked with the kernel. It was not as simple as modifying CONFIG.SYS and rebooting – PC/MS-DOS sysadmin skills did not transfer over. And it couldn't usefully run Windows. So as soon as Windows 3 came out in 1990 and the market started to move to Windows and Windows apps, that was largely it for Concurrent DOS, PC-MOS etc. When DR was bought out by Novell, several forks of the codebase were continued for a while by OEM licencees, and it gained support for FAT32, USB and so on. A branch of the CDOS codebase is still just about alive though. DR did a 286 version, but were screwed over by Intel. CDOS286 used a feature of prototype 80286 chips to multitask DOS apps, but this was removed in the final shipping CPU hardware. (Intel did not know and put it back but it was too late.) DR just took the OS in a different direction and sold it as a multitasking real-time OS instead, downplaying DOS compatibility. It bundled a multitasking version of its GEM desktop, too, so it was a multitasking GUI RTOS, called DR-FlexOS. This found a niche in electronic point-of-sale systems: EPOS, i.e. smart cash registers built around x86 PCs. It was later acquired by IBM who rebranded it as IBM 4680 OS, later IBM 4690 OS. (What a knack for snappy names Big Blue has!) IBM discontinued it just a few years ago, but it is still sold by Toshiba.