IDirectMusicSynth::GetFormat method (dmusics.h)

Articolo
12/05/2018

The GetFormat method retrieves information about the wave format.

Syntax

HRESULT GetFormat(
  LPWAVEFORMATEX pWaveFormatEx,
  LPDWORD        pdwWaveFormatExSize
);

Parameters

pWaveFormatEx

Pointer to a caller-allocated WAVEFORMATEX structure into which the method writes information about the format. This value can be NULL. For more information, see the following Remarks section.

pdwWaveFormatExSize

Pointer to a caller-allocated DWORD variable specifying the size in bytes of the structure that pWaveFormatEx points to. For more information, see the following Remarks section.

Return value

GetFormat returns S_OK if the call was successful. Otherwise, the method returns an appropriate error code. The following table shows some of the possible return status codes.

Return code	Description
E_POINTER	Indicates that one of the pointers is not valid.
DMUS_E_SYNTHNOTCONFIGURED	Indicates that the synth is not open or is not properly configured.

Remarks

The WAVEFORMATEX structure can have a variable length that depends on the details of the format. Therefore, before retrieving the format description, an application will first query the IDirectMusicSynth object for the size of the format by calling this method and specifying NULL for the pWaveFormatEx parameter. In this case, the synth should return the size of the structure in the pdwWaveFormatExSize parameter. The application can then allocate sufficient memory and call IDirectMusicSynth::GetFormat again to retrieve the format description.

If the pWaveFormatEx parameter is not NULL, DirectMusic writes, at most, pdwWaveFormatExSize bytes to pWaveFormatEx.

For more information, see the description of the IDirectMusicPort interface and IDirectMusicPort::GetFormat method in the Microsoft Windows SDK documentation.

Requirements

Requirement	Value
Target Platform	Desktop
Header	dmusics.h (include Dmusics.h)

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