Maurice Kinal wrote in a message to Jasen Betts:

 MK> Hey Jasen!

 MK> Sep 15 09:51 04, Jasen Betts wrote to Maurice Kinal:

 JB> CP/M mostly, that's where it got / for options instead of -

 MK> That's where that came from.  DOS more reminded me of VMS but then
 MK> again I have no experience with CP/M so that would explain that.

I do,  and that's not where that came from.  And also,  it's possible for a
dos program to use either,  depending on how things are set up.  I had
occasion to work with the "Wang PC" back about 1985 or so,  where
the - was used instead of a / all the time.  Weird machine,  that,  you had
a  key _and_ an  key on the keyboard,  which did
different things.

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