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IOCTL_AG_GET_SPEAKER_VOL (Compact 2013)

  • Article

3/26/2014

This I/O control message retrieves the speaker volume of the headset or the hands-free device. Send this message with DeviceIoControl.

Syntax

BOOL DeviceIoControl(
    HANDLE hDevice,           // handle to device
    DWORD dwIoControlCode,    // use IOCTL_AG_GET_SPEAKER_VOL
    LPVOID lpInBuffer,        // pointer to input buffer
    DWORD nInBufferSize,      // input buffer size
    LPVOID lpOutBuffer,       // pointer to output buffer
    DWORD nOutBufferSize,     // output buffer size
    LPDWORD lpBytesReturned,  // number of bytes returned
    OVERLAPPED lpOverlapped   // pointer to OVERLAPPED structure
);

Parameters

  • hDevice
    The handle to the device.
  • dwIoControlCode
    [in] Control code for the operation. Use IOCTL_AG_GET_SPEAKER_VOL for this operation.
  • lpInBuffer
    Not used; set to NULL.
  • nInBufferSize
    Not used; set to zero.
  • lpOutBuffer
    [out] Points to a USHORT variable that receives the speaker volume.
  • nOutBufferSize
    [in] sizeof(USHORT).
  • lpBytesReturned
    [out] Set to cOutBuffer.
  • lpOverlapped

Remarks

To set the speaker volume, use the IOCTL_AG_SET_SPEAKER_VOL I/O control.

Requirements

Header

btagpub.h

See Also

Reference

Bluetooth AG Service IOCTL Messages