A/UX is SVID-compatible and SVVS Issue 1 & 2 certified.
SVID (System V Interface Definition) is a set of specifications (somewhat
like manual pages), of how internal components -- such as system calls,
parameters, etc. -- should look. This specification standard allows a
higher degree of code portability to other machines.
SVVS (System V Validation Suite) Issue 2 is a series of programs for System
V.2 that test the System V.2 porting for about 4-5 hours. If the tests are
passed with no modification, the porting (in this case, A/UX) is said to be
SVID-compatible.
A/UX Version 1.0 is SVID-compatible. It passes the SVVS Issue 2
certification tests. (Issue 2 is in fact the latest and only appropriate
release for our system.)
(NOTE: There is a paragraph stating SVVS-conformance on the back of the
cover page of the A/UX Release Notes.)
Not only does A/UX pass the standard test with no modifications required,
but it also passes the optional Kernel Extensions test, which is not
required for SVID-compatibility.