SunOS is a version of the Unix operating system developed by Sun Microsystems for their workstation and server computer systems. The SunOS name is usually only used to refer to versions 1.0 to 4.1.4 of SunOS. These versions were based on BSD Unix, while SunOS version 5.0 and later are based on UNIX System V Release 4, and are marketed under the brand name Solaris.
|SunOS version||Release date||Code base||Description|
|Sun UNIX 0.7||1982||UniSoft UNIX v7||Bundled with 68000-based Sun-1 system|
|SunOS 1.0||1983||4.1BSD||Support for 68010-based Sun-1 and Sun-2 systems|
|SunOS 1.1||Apr 1984|
|SunOS 1.2||Jan 1985|
|SunOS 2.0||May 1985||4.2BSD||Introduced virtual file system (VFS) layer and the NFS protocol|
|SunOS 3.0||Feb 1986||4.2BSD + System V IPC||coincided with release of 68020-based Sun-3 series. Optional System V tape offered utilities and development libraries.|
|SunOS 3.2||Sep 1986||Same as 3.0, plus some 4.3BSD||First support for Sun-4 series|
|SunOS 3.5||Jan 1988|
|SunOS 4.0||Dec 1988||4.3BSD with System V IPC||New virtual memory system, dynamic linking, automounter, System V STREAMS I/O. Sun386i support.|
|SunOS 4.0.2||Sep 1989||Sun386i only|
|SunOS 4.0.3||May 1989|
|SunOS 4.0.3c||Jun 1989||SPARCstation 1 (Sun-4c) only|
|SunOS 4.1||Mar 1990|
|SunOS 4.1e||Apr 1991||Sun-4e only|
|SunOS 4.1.1||Mar 1990||Bundled with OpenWindows 2.0|
|SunOS 4.1.1B||Feb 1991|
|SunOS 18.104.22.168||Jul 1991|
|SunOS 4.1.1_U1||Nov 1991||Sun-3/3x only|
|SunOS 4.1.2||Dec 1991||Support for multiprocessor (SPARCserver 600MP) systems; first CD-ROM-only release|
|SunOS 4.1.3||Aug 1992|
|SunOS 4.1.3C||Nov 1993||SPARCclassic/SPARCstation LX only|
|SunOS 4.1.3_U1||Dec 1993|
|SunOS 4.1.3_U1B||Feb 1994||Earliest release for which Y2K compliance patches were available|
|SunOS 4.1.4||Nov 1994||Last release of SunOS 4|
|SunOS 5.x||Jun 1992 -||SVR4||See Solaris article|
SunOS 1 and 2 supported the Sun-2 series systems, including Sun-1 systems upgraded with Sun-2 (68010) CPU boards. SunOS 3 supported Sun-2 and Sun-3 (68020) series systems. SunOS 4 supported Sun-2 (until release 4.0.3), Sun-3 (until 4.1.1), Sun386i (4.0, 4.0.1 and 4.0.2 only) and Sun-4 (SPARC) architectures. Although SunOS 4 was intended to be the first release to fully support Sun's new SPARC processor, there was also a SunOS 3.2 release with preliminary support for Sun-4 systems.
SunOS 4.1.2 introduced support for Sun's first sun4m-architecture multiprocessor machines (the SPARCserver 600MP series); since it had only a single lock for the kernel, only one CPU at a time could execute in the kernel.
In 1987, AT&T and Sun announced that they were collaborating on a project to merge the most popular Unix flavors on the market at that time: BSD (including many of the features then unique to SunOS), System V, and Xenix. This would become System V Release 4 (SVR4).
On September 4 1991, Sun announced that its next major OS release would switch from its BSD-derived source base to one based on SVR4. Although the internal designation of this release would be SunOS 5, from this point Sun began using the marketing name Solaris. The justification for this new "overbrand" was that it encompassed not only SunOS, but also the OpenWindows desktop environment and Open Network Computing (ONC) functionality.
Even though the new SVR4-based OS was not expected to ship in volume until the following year, Sun immediately began using the new Solaris name to refer to the currently shipping SunOS 4 release (also including OpenWindows). Thus SunOS 4.1.1 was rechristened Solaris 1.0; SunOS 5.0 would be considered a part of Solaris 2.0. SunOS 4.1.x micro versions continued to be released through 1994, and each of these was also given a Solaris 1.x equivalent name. In practice, these were often still referred to by customers and even Sun personnel by their SunOS release names. Matching the version numbers was not straightforward:
|SunOS Version||Solaris Version||OpenWindows Version|
|4.1.3||1.1 SMCC Version A||3.0|
Today, SunOS 5 is universally known as Solaris, although the SunOS name is still visible within the OS itself—in the startup banner, the output of the uname command, and man page footers, among other places.
Matching a SunOS 5.x release to its corresponding Solaris marketing name is simple: each Solaris release name includes its corresponding SunOS 5 minor version number. For example, Solaris 2.4 incorporated SunOS 5.4. There is one small twist: after Solaris 2.6, the "2." was dropped from the Solaris name and the SunOS minor number appears by itself. The latest Solaris release is Solaris 10 and incorporates SunOS 5.10.