Phillip Remaker
user of dozens of common and uncommon operating systems.Updated 8y
Microsoft did, in fact, have a Unix based operating system called Xenix in the late-DOS early-Windows timeframe. I had a PC/AT (80286 based) in 1989 running Xenix with about 1MB (yes, MB) of memory. It was never more than a niche product for Microsoft.
You have to remember that the Microsoft of the 1980s was writing software for the personal computers of the time, which were significantly underpowered relative to the so-called minicomputers running Unix at the time. Multiuser was not an issue for Microsoft (it was, after all, a “personal” computer) and even running multiple apps at the same time was not a priority.
The first class of OSes that Microsoft made were really nothing more than primitive program loaders. Although Windows added a GUI, it only added multi-application capability later in its evolution. Prior to Windows NT, Windows never had serious really multi-user capability because the underlying filesystem had no sense of multiple users or anything more than primitive file security. Windows for Workgroups added multi-user, but only network based files had any file security.
Windows NT (the ancestor of modern Windows) was Microsoft’s first serious multi-user OS. Windows NT attempted to leapfrog Unix with a more sophisticated sense of system and user identity as well as much more fine grained access control in the file system, including a well defined distributed directory (Active Directory). A lot of what Windows did was, in fact, superior to the ancestral models of file access, distributed directory and user identity in Unix. Their development team came out of DEC, so the roots of the OS have more in common with VMS than Unix.
Consider also that the Unix licensing was a wild mess in the Windows NT era. Lawyers in 1993 might be nervous about AT&T asserting their rights to Unix. The USL v. BSDi lawsuit cast a long shadow over the future of Unix. Most “free” variants of Unix descended from BSD, which was on shaky ground as a product that could be commercially sold. If Microsoft wanted to make a commercial Unix, they would either have to risk being sued or pay royalties to AT&T. Coming off a troubled and tumultuous relationship with IBM, Microsoft elected to forge a path ahead where they controlled their own destiny.
16.7K views
View 154 upvotes