winmm: Test opening the same device twice

Eric Pouech eric.pouech at
Tue Aug 19 12:36:14 CDT 2008

Maarten Lankhorst a écrit :
> Behavioral test to show that wine winmm needs fixing.
> ---
> ------------------------------------------------------------------------
this likely is going to fail on old boxes
there's no requirement on MS side that a PCM renderer has to be opened twice
so having it as a test is wrong
some old cards with OSS as a driver forbid the card to be opened twice 
(especially in different processes). IIRC, there was a bit of support in 
the OSS driver (not sure about the ALSA one) to allow > 1 opening in the 
same process (and also opening one handle for sound capture and another 
one for sound rendering).
but this didn't provide support for mixing the output from the two 
different handles, which is likely what part of what you're trying to do 
assumes (especially for dsound plus standard winmm output)

the only way out is to have the Linux (or Unix) driver handle several 
opening including the mixing of the two streams
if the driver doesn't provide this flexibility, I don't see a point of 
implementing it in Wine


Eric Pouech
"The problem with designing something completely foolproof is to underestimate the ingenuity of a complete idiot." (Douglas Adams)

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