DirectX SDK

IDirectSoundBuffer::Unlock

The IDirectSoundBuffer::Unlock method releases a locked sound buffer.

HRESULT Unlock(
  LPVOID lpvAudioPtr1, 
  DWORD dwAudioBytes1, 
  LPVOID lpvAudioPtr2, 
  DWORD dwAudioBytes2  
);

Parameters

lpvAudioPtr1
Address of the value retrieved in the lplpvAudioPtr1 parameter of the IDirectSoundBuffer::Lock method.
dwAudioBytes1
Number of bytes actually written to the lpvAudioPtr1 parameter. It should not exceed the number of bytes returned by the IDirectSoundBuffer::Lock method.
lpvAudioPtr2
Address of the value retrieved in the lplpvAudioPtr2 parameter of the IDirectSoundBuffer::Lock method.
dwAudioBytes2
Number of bytes actually written to the lpvAudioPtr2 parameter. It should not exceed the number of bytes returned by the IDirectSoundBuffer::Lock method.

Return Values

If the method succeeds, the return value is DS_OK.

If the method fails, the return value may be one of the following error values:

DSERR_INVALIDCALL
DSERR_INVALIDPARAM
DSERR_PRIOLEVELNEEDED

Remarks

An application must pass both pointers, lpvAudioPtr1 and lpvAudioPtr2, returned by the IDirectSoundBuffer::Lock method to ensure the correct pairing of IDirectSoundBuffer::Lock and IDirectSoundBuffer::Unlock. The second pointer is needed even if 0 bytes were written to the second pointer.

Applications must pass the number of bytes actually written to the two pointers in the parameters dwAudioBytes1 and dwAudioBytes2.

Make sure the sound buffer does not remain locked for long periods of time.

Requirements

  Windows NT/2000: Requires Windows NT 4.0 SP3 or later.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in dsound.h.
  Import Library: Use dsound.lib.

See Also

IDirectSoundBuffer, IDirectSoundBuffer::GetCurrentPosition, IDirectSoundBuffer::Lock