ISpMMSysAudio::GetLineId (SAPI 5.4)

Speech API 5.4
Microsoft Speech API 5.4


ISpMMSysAudio::GetLineId retrieves the current line identifier associated with the multimedia device. Mixer lines are not supported for output devices.

   UINT   *puLineId


[out] Address of the structure that receives the line identifier information.

Return values

S_OKFunction completed successfully.
E_NOTIMPLNot implemented for output devices.
E_POINTERpuLineId is invalid.
SPERR_NOT_FOUNDThe audio device must have been created from a token.
FAILED(hr)Appropriate error message.


For more information on the uses of device lines, please see the Win32 multimedia mixer API (e.g., mixerOpen, mixerGetId, mixerGetLineInfo, etc.)

For input devices, SAPI will attempt to automatically identify the microphone line on the input device. On non-English versions of Windows and on a small number of English systems, it may not be possible for SAPI to automatically detect the correct microphone line. In this case, no error will be detected or returned. In such cases, if speech input is not correctly detected, the user must set the microphone input line directly using Control Panel-->Speech properties-->Speech Recognition tab-->Audio Settings-->Properties. In particular, this may be necessary to adjust the microphone input line used on devices with multiple microphone inputs such as the SoundBlaster Live Platinum as the automatically chosen line may not be the input preferred by the user.