Microsoft Windows CE 3.0  


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This message notifies an ACM driver of changes to other ACM drivers.


Specifies a driver instance identifier. The driver returns this value in response to the ACM_Openfunction.
Handle to a driver.
Specifies this message.
Not used.
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.


Each time a client calls the acmDriverAdd, acmDriverRemove, or acmDriverPriorityfunctions, the ACM (Waveapi.dll) sends this message by calling the ACM driver's ACM_IOControlentry point through the DeviceIoControlfunction. For more information about these functions, see the Windows CE Platform SDK.

ACM driver support for this message is optional. If the driver supports this message, it can call ACM functions, such as acmEnumDriversand acmMetrics, to determine which drivers have been added, removed, enabled, disabled, or changed in priority. However, Windows CE versions 2.12 and earlier do not issue this message because ACM drivers cannot be dynamically added or removed, and their priorities are fixed.


Runs on Versions Defined in Include Link to
Windows CE OS 3.0 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

© 2004 Microsoft Corporation. All rights reserved.