That parenthetical history is wrong, at least according to Dave Cutler.  He traced Windows NT&#x27;s threading back to his work on VAXELN in 1983, years before POSIX was even thought of.  He also was quite obviously deriving the NT API in part from OS&#x2F;2, again not POSIX, given the whole &quot;mutant&quot;&#x2F;&quot;mutex&quot; affair.