At one time there was a lot of zombie processes lingering for a long-ish time until the parent terminated and the zombies were reaped by init. I didn't bother to look at the implementation for xpopen, as I assumed it was just a call to popen. Turned out it wasnt; it was fork/exec with a socketpair turned into a FILE* with fdopen. The child was not waited for in xpclose.

I think there can be times when the facade pattern makes sense. I think there can be times when importing the world makes sense. I think there can be times when the opposite is true too. I think talking about these things in an abstract way can miss the point of the very insanity in some concrete solutions out there.