@swagpussc (...continued)
Often forgotten by people is the period in between. The people who cloned Linux and the (GNU) "shell" around it often worked from samizdat doco about 1970s Unix.

In the 1980s and early 1990s, there were a whole bunch of commercial #Unix flavours: #Xenix, HP/UX, #AIX, #SunOS, #Ultrix, OSF/1, AT&T System 3, AT&T System 5, ...

#Illumos, which came from #Solaris, which came from SunOS, is actually still around.

https://illumos.org

#SVR3 #SVR5
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