Yeah, but POSIX was just codifying the proprietary UNIX standards. UNIX got bootlegged in a era where license enforcement wasn't strict because people didn't even know what licenses where. These days UNIX would have been a strictly proprietary AT&T product, from day 1.
Heck, POSIX stands for Portable Operating System (POS) + IX because X is a cool letter and IX because POSIX is cooler than POSIX plus, you know, UNIX.
"Were all Unix commands re-written in Linux?"' https://unix.stackexchange.com/questions/85189/were-all-unix...
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