[TUHS] /usr/mdec

Dave Horsfall dave at horsfall.org
Mon Nov 21 14:25:43 AEST 2022

On Sun, 20 Nov 2022, Norman Wilson wrote:

> I'm curious about the origin of the directory name /usr/mdec. (I am 
> reminded of it because I've noticed that it lives on in at least one of 
> the BSDs.)
> I had a vague notion that it meant `DEC maintenance' but that seems a 
> bit clumsy to describe a place holding boot blocks.

As far as I know, that's right; MAINDEC was certainly on all of their 
standalone diagnostic media (a beauty was DECEX, which thrashed the PDP-11 
and uncovered a bug in our RK-11 controller; it screwed up on overlapped 
seeks which RSX didn't use but Harvard(?) did, so DEC's view was that it 
was obviously a Unix problem).

-- Dave

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