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.

QuickInfo

  Windows NT: Use version 4.0 or later.
  Windows: Use Windows 95 OSR2 or later. Available as a redistributable for Windows 95.
  Windows CE: Unsupported.
  Header: Declared in dsound.h.
  Import Library: Use dsound.lib.

See Also

IDirectSoundBuffer, IDirectSoundBuffer::GetCurrentPosition, IDirectSoundBuffer::Lock