On Wed, Sep 11, 2019 at 1:52 PM <ron@ronnatalie.com> wrote:

> The Pyramid OS used “conditional symlinks” if I recalled to implement
> switching the bin directories.
>
> The UCLA LOCUS/IBM Transparent Computing Facility switched versions of
> executables by using a “magic” directory that was conditional on the cpu
> type.
>
Right, TCF did that (Bruce built them IIRC).

As I said, I resurrected CSDL's from Masscomp at Locus for TNC which was
more general and lost less intrusive (which is how they landed in Tru64
when we sold the TNC to DEC to become TruClusters and I would join them).
As for CDSL, I had generalized it for LCC from what I did at Masscomp years
before.

FWIW: I still think they are a cute idea and solve a number of problems,
but alas they are no longer ;-)