acmDriverEnum function (msacm.h)

The acmDriverEnum function enumerates the available ACM drivers, continuing until there are no more drivers or the callback function returns FALSE.

Syntax

MMRESULT ACMAPI acmDriverEnum(
  ACMDRIVERENUMCB fnCallback,
  DWORD_PTR       dwInstance,
  DWORD           fdwEnum
);

Parameters

fnCallback

Procedure instance address of the application-defined callback function.

dwInstance

A 64-bit (DWORD_PTR) or 32-bit (DWORD) application-defined value that is passed to the callback function along with ACM driver information.

fdwEnum

Flags for enumerating ACM drivers. The following values are defined.

Value Meaning
ACM_DRIVERENUMF_DISABLED Disabled ACM drivers should be included in the enumeration. Drivers can be disabled by the user through the Control Panel or by an application using the acmDriverPriority function. If a driver is disabled, the fdwSupport parameter to the callback function will have the ACMDRIVERDETAILS_SUPPORTF_DISABLED flag set.
ACM_DRIVERENUMF_NOLOCAL Only global drivers should be included in the enumeration.

Return value

Returns zero if successful or an error otherwise. Possible error values include the following.

Return code Description
MMSYSERR_INVALFLAG
At least one flag is invalid.
MMSYSERR_INVALPARAM
At least one parameter is invalid.

Remarks

The acmDriverEnum function will return MMSYSERR_NOERROR (zero) if no ACM drivers are installed. Moreover, the callback function will not be called.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header msacm.h
Library Msacm32.lib
DLL Msacm32.dll

See also

Audio Compression Functions

Audio Compression Manager