Avoid collisions between parallel installations of Cygwin

[Earnie Boyd]

Quoting Corinna Vinschen <corinna-cygwin@cygwin.com>:

>
> As I noted above, the potential problems aren't really new, given at
> least the existence of MSYS.  MSYS exists for many years now.  Have you
> searched the list for problems which have been reduced to the
> co-existance of MSYS and Cygwin on the same machine?  I didn't, but then
> again, I can't remember any of them.  If there are some, they are very,
> very seldom for sure.
>

I know they can exist.  One of the post install steps performed by  
MSYS install is to check if CYGWIN is on the windows PATH and tell the  
user to remove it.  However, they exist only because of the Cygwin  
multiple instance issues.  When Cygwin matched MSYS more than it does  
now I did successfully execute Cygwin binaries from within MSYS.  I  
haven't tried recently.

> So, here's your next question:  Given that there are no or so few
> problem reports which could be tracked down to a MSYS/Cygwin
> co-existance problem, does that mean the potential problems are
> exaggerated, or does that mean we just didn't detect the cause of the
> problem?  As you can easily guess, I have no answer to this question.
>

Probably exaggerated.  Any report of clashed issues on the MinGW lists  
because of MSYS and CYGWIN always result in the user needing to remove  
the cygwin/bin from the windows PATH.  We also discourage the user  
from modifying the windows PATH for MinGW binaries including MSYS.

--
Earnie