Common Open Software Environment

The Common Open Software Environment or COSE was an initiative formed in March 1993 by the major Unix vendors of the time to create open, unified operating system (OS) standards.

The COSE process was established during a time when the "Unix wars" had become an impediment to the growth of Unix. Microsoft, already dominant on the corporate desktop, was beginning to make a bid for two Unix strongholds: technical workstations and the enterprise data center. In addition, Novell was seeing its NetWare installed base steadily eroding in favor of Microsoft-based networks; as part of a multi-faceted approach to battling Microsoft, they had turned to Unix as a weapon, having recently formed a Unix-related partnership with AT&T known as Univel.

Unlike other Unix unification efforts that preceded it, COSE was notable in two ways: it was not formed in opposition to another set of Unix vendors, and it was more oriented toward making standards of existing technologies than creating new offerings from scratch.

The initial members, (known as "The Big Six" or "SUUSHI"), were:

These represented the significant Unix system and OS vendors of the time, as well as the holders of the Unix brand and AT&T-derived source code. They also represented almost all the key players in the two major Unix factions of the late 1980s and early 1990s, the OSF and Unix International (UI). Notable in its absence was OSF co-founder Digital Equipment Corporation; Digital did finally announce its endorsement of the COSE process the following June.

COSE's announced areas of focus were: a common desktop environment; networking; graphics; multimedia; object-based technology; and, systems management. On September 1, 1993 it was also announced that the COSE vendors were developing a unified Unix specification with the support of over 75 companies.

Unlike OSF or UI, the COSE initiative was not tasked to create or promote a single operating system. Their approach was to instead survey and document the OS interfaces already in use by Unix software vendors of the time. This resulting list, originally known as "Spec 1170", evolved to become what is now known as the Single Unix Specification.

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