Comment by whobre
1 day ago
< Rewind to 1973. The operating system common on microcomputers was CP/M
OK. I love Raymond’s blog but this is crazy. Microcomputers existed only as a prototype in 1973 (things like Intel’s Intellec dev systems) and there were no operating systems for them. Strictly speaking, Kildall did start developing CP/M in 1973, but at that point it ran only on a simulator on a PDP-10 mainframe.
1979, sure. 1973? Way too early…
Wikipedia says it was created in 1974, so something's definitely off with the time line here.
Intel 8080 was launched in April 1974 and the development system for it, "Intellec 8 Mod 80", was available soon after that.
CP/M could be developed only after the launch of the 8080 and the delivery of the development system.
In UNIX, the environment variables were added in the Seventh Edition (1979-01), together with the Bourne shell.
I do not remember whether any other command interpreters used something equivalent with environment variables before the UNIX shell (excluding the interpreters for general-purpose programming languages, like LISP and APL, where you can run a function in REPL and that function can access global variables).
Therefore the quoted year may be a typo for 1979, when environment variables appeared in the UNIX shell, but were not available in the CP/M Console Command Processor (CCP, the predecessor of COMMAND.COM).
> 1979, sure. 1973? Way too early…
Which is fun, because this is the same time difference between 2020 and now
And then we think we didn't have ChatGPT in 2020