ACMDM_DRIVER_ABOUT

This message requests an ACM driver to display its About dialog box.

Parameters

  • dwDriverID
    Specifies a driver instance identifier. The driver returns this value in response to the ACM_Open function.
  • hDriver
    Handle to a driver.
  • uMsg
    Specifies this message.
  • lParam1
    Contains a validated window handle, which the driver should use to specify the parent window for the About dialog box. The value also can be –1L.
  • lParam2
    Not used.

Return Values

MMSYSERR_NOERROR indicates success. Otherwise, the driver returns one of the MMSYSERR error values declared in the Mmsystem.h header file or one of the ACMERR error values declared in the Msacm.h header file. If the driver does not provide an About dialog box, it returns MMSYSERR_NOTSUPPORTED.

Remarks

The ACM (Waveapi.dll) sends this message by calling the ACM driver's ACM_IOControl function entry point through the DeviceIoControl function.

If an ACM driver provides an About dialog box, it displays the box in response to this message. If an ACM driver does not provide an About dialog box, it returns MMSYSERR_NOTSUPPORTED. In the latter case, the ACM displays a default About dialog box.

However, if lParam1 is –1L, the driver does not display its About dialog box. Instead, it returns MMSYSERR_NOERROR if it provides an About dialog box and MMSYSERR_NOTSUPPORTED if it does not provide an About dialog box.

For more information, see the Microsoft Windows NT DDK.

Requirements

Runs on Versions Defined in Include Link to
Windows CE OS 1.0 and later      

Note   This API is part of the complete Windows CE OS package as provided by Microsoft. The functionality of a particular platform is determined by the original equipment manufacturer (OEM) and some devices may not support this API.

 Last updated on Tuesday, July 13, 2004

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