Windows Services for UNIX

Not to be confused with Windows Subsystem for Linux.
Windows Services for UNIX
Other namesSFU
Original author(s)MKS Inc. (SFU 1.0 / 2.0), Softway Systems, Inc. (SFU 3.0 / 3.5)
Developer(s)Microsoft
Initial releaseFebruary 1999; 25 years ago (1999-02)
Final release
3.5 / January 2004; 20 years ago (2004-01)
Operating systemMicrosoft Windows
PlatformIA-32 and x86-64
PredecessorMicrosoft POSIX subsystem
SuccessorWindows Subsystem for Linux
TypeCompatibility layer
WebsiteWindows Services for Unix at the Wayback Machine (archived 2017-08-26)

Windows Services for UNIX (SFU) is a discontinued software package produced by Microsoft which provided a Unix environment on Windows NT and some of its immediate successor operating-systems.

SFU 1.0 and 2.0 used the MKS Toolkit; starting with SFU 3.0, SFU included the Interix subsystem,[1] which was acquired by Microsoft in 1999 from US-based Softway Systems as part of an asset acquisition.[2] SFU 3.5 was the last release and was available as a free download from Microsoft. Windows Server 2003 R2 included most of the former SFU components (on Disk 2), naming the Interix subsystem component Subsystem for UNIX-based Applications (SUA).[3] In Windows Server 2008 and high-end versions of both Windows Vista and Windows 7 (Enterprise and Ultimate), a minimal Interix SUA was included, but most of the other SFU utilities had to be downloaded separately from Microsoft's web site.[1]

The Interix subsystem included in SFU 3.0 and 3.5 and later released as SUA Windows components provided header files and libraries that made it easier to recompile or port Unix applications for use on Windows; they did not make Linux or other Unix binaries (BSD, Solaris, Xenix etc) compatible with Windows binaries. Like the Microsoft POSIX subsystem that Interix replaced, it is best thought of as a distinct Unix-like platform.

It is replaced by Windows Subsystem for Linux in Windows 10 and Windows Server 2019.

  1. ^ a b Dale Liu; Justin Peltier (2008). Next Generation SSH2 Implementation: Securing Data in Motion. Syngress. pp. 181–182. ISBN 978-1-59749-283-6. Archived from the original on September 30, 2014. Retrieved October 26, 2016.
  2. ^ "Microsoft Acquires Softway Systems to Strengthen Future Customer Interoperability Solutions" (Press release). Microsoft. September 17, 1999. Archived from the original on February 22, 2011. Retrieved December 28, 2010.
  3. ^ "Subsystem for UNIX-based Applications Overview". Microsoft. November 17, 2009. Retrieved August 20, 2022.