The Mac is Dead! Long Live the Wintel PC! was Apple ahead of schedule 3110
Yes, exactly. A Disk Operating System operates the disks - and that's all that DOS directly controls. Everything else - printers, video, memory management, serial ports - was managed by the apps that used them, or by add-ons or "DOS extenders". That's why every DOS app you installed came with it's own printer drivers, for example.
Hayes) Actually, "DOS" is "command.com", "msdos.sys", and "io.sys" combined. "command.com" is just the command interpreter (shell). msdos.sys and io.sys are the "kernal". "QDOS" was indeed...
A true Operating System runs the whole show. Apps make OS calls to get memory or to print a character to the printer, and the apps don't need to know the details of how much memory is available or what kind of printer is installed. The OS handles the details. The OS controls the access to the hardware.
If you think that DOS is an Operating System then you don't know very much about either. DOS + Windows 3.11 + Mouse.sys + Himem.sys (or QEMM386.sys) + Smartdrv.sys was an Operating System. An ugly kludge to be sure, but an Operating System none the less.
Windows 95 combined all of these various bits and pieces into a single package, and hence was an Operating System. Still a kludge, but easier to install and better integrated.
Mike