"Spec 1170" was the working name of the standard UNIX programming interface specification that is now known as X/Open Programming Guide 4.2 (XPG 4.2). The specification has also been known as the "Single UNIX Specification" and, most recently, as "UNIX 98." In the "Spec 1170" or first version of the Single UNIX Specification, there were 1,170 C language functions or individual instructions.
The Single UNIX Specification is maintained by The Open Group, which certifies implementations and provides UNIX product branding following conformance assurance and testing.
This was last updated in November 1997