This argument is becoming a little absurd. The lede talks about "Single UNIX Specification (SUS)". It then immediately moves to "UNIX Operating systems" (plural) and then "most UNIX-like operating systems" (again a plural). If that wasn't enough, Tedickey immediately talks about "X/Open"; and then somehow "Posix" makes its way into the conversation. If there's no agreement on even that, it seems pointless to continue the discussion. Finally, Tedickey, as to your "(a) little-used applications, (b) Linux-specific, or (c) developers promoting their products. ", categories, into which of those are you going to fit mknod?