Bell Labs, the developer of Unix, was part of the regulated Bell System and could not sell Unix directly to most end users (academic and research institutions excepted); it could, … 展开

Aside from its AT&T Unix base, Xenix incorporated elements from BSD, notably the vi text editor and its supporting libraries (termcap and curses). Its kernel featured some original extensions by Microsoft, notably file locking and semaphores, … 展开

• AT&T 6300 Plus
• Concurrent DOS
• PC/IX
• Venix 展开

• "SCO Xenix". Archived from the original on 2010-01-23. Retrieved 2005-10-25.
• Xenix timeline
• Xenix documentation and books for Download Archived 2014-10-21 at the Wayback Machine 展开

Trusted Xenix was a variant initially developed by IBM, under the name Secure XENIX; later versions, under the Trusted Xenix name, were developed by Trusted Information Systems. … 展开

• Christian, Kaare (1984-05-29). "A UNIX to be Proud Of". PC Magazine: 165–172. ISSN 0888-8507.; review of the beta SCO Xenix on an XT 展开