Not the GP, but I have one non-partioning AIX trivia I discovered by accident. Turns out that malloc(0) returns NULL on AIX, but non-null on Linux, SunOS, and Irix. (I was surprised multiple ways on that one!)

Sometimes I think "it's a UNIX system, I know this" but I've been caught by subtle differences before too.

killall is very different between Linux and Solaris, for example. I would rather have not found this out on a client machine for the first time.

Another AIX different that caughts folks off guard, it uses COFF primarly, and its dynamic library models is closer to Windows, OS/2, Symbian, than classical UNIX with ELF.

Including the existence of import libraries, linker export files, and lazy dynamic loading of symbols.

Now that you know, can you conceptualize reasons why each pattern might be a correct preference? Among those reasons, which would you prefer as a system?

^^^ THAT is how an Interview Question should work around this factoid.

That one has bitten me more than once

Gah, I can't remember what the specific trivia was now (ironically), just that some disk wasn't mounting and something in the fstab stuck out to me that I then looked up in the manpages and confirmed was wrong. (I wasn't even the AIX guy, I was just the sysadmin of an app that ran on AIX.)