Recording What-You-Hear audio in Windows 7 [duplicate]

This question already has an answer here: Closed 11 years ago.

Possible Duplicate:

Windows Vista/7: How to sample output audio mix?

How 开发者_如何学运维to record what-you-hear audio stream in Windows with C/C++?

The solution should be compatible with Windows 7 where, AFAIK, some changes has been introduced about that. As a result, some programs (CamStudio) are unable to record W-Y-H sound while others still are (Camtasia, TotalRecorder). How do they do that?

If I'm wrong and there is none restriction I'm just interesting in how to start to listen and record that audio stream.

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You can do so with WASAPI. There's a loopback sample available that I used a while back to learn how. It will only work on Vista and up, though -- not XP.

I've not tried to do it pre-Vista, so I don't know for sure why any old APIs would stop working.