Editing UNIX System V (section)

=== Rivalry with BSD ===
{{Main|Unix wars}}
In the 1980s and early-1990s, UNIX System V and the [[Berkeley Software Distribution]] (BSD) were the two major versions of UNIX. Historically, BSD was also commonly called "BSD Unix" or "Berkeley Unix".<ref>Garfinkel, Simson. Spafford, Gene. Schwartz, Alan. ''Practical UNIX and Internet Security.'' 2003. pp. 15-20</ref> [[Eric S. Raymond]] summarizes the longstanding relationship and rivalry between System V and BSD during the early period:<ref>Raymond, Eric S. ''The Art of Unix Programming.'' 2003. p. 38</ref>

{{quote|In fact, for years after divestiture the Unix community was preoccupied with the first phase of the [[Unix wars]]&nbsp;– an internal dispute, the rivalry between System V Unix and BSD Unix. The dispute had several levels, some technical ([[Berkeley sockets|sockets]] vs. [[STREAMS|streams]], BSD tty vs. System V termio) and some cultural. The divide was roughly between longhairs and shorthairs; [[programmer]]s and technical people tended to line up with Berkeley and BSD, more business-oriented types with AT&T and System V.}}

While HP, IBM and others chose System V as the basis for their Unix offerings, other vendors such as [[Sun Microsystems]] and [[Digital Equipment Corporation|DEC]] extended BSD. Throughout its development, though, System V was infused with features from BSD, while BSD variants such as DEC's [[Ultrix]] received System V features. AT&T and Sun Microsystems worked together to merge System V with BSD-based [[SunOS]] to produce [[Solaris (operating system)|Solaris]], one of the primary System V descendants still in use today{{When|date=December 2019}}. Since the early 1990s, due to standardization efforts such as [[POSIX]] and the success of [[Linux]], the division between System V and BSD has become less important.