This is a limitation we need to (unfortunately) accept on AIX. 

These lines are a combination of two commits:
https://github.com/andrewlow/node/commit/c1d565ba92ab1eb3c6950904653b8fb19b938405
https://github.com/andrewlow/node/commit/0edef8289a44fd67c631cdb15bc9060bee68c522

AIX lacks socket introspection support for AF_UNIX sockets, however the standard I/O pipes also look just like a socket to this code so we have to hope it is the usual case.