ACMDRIVERENUMCB callback function (msacm.h)
The acmDriverEnumCallback function specifies a callback function used with the acmDriverEnum function. The acmDriverEnumCallback name is a placeholder for an application-defined function name.
Syntax
ACMDRIVERENUMCB Acmdriverenumcb;
BOOL Acmdriverenumcb(
HACMDRIVERID hadid,
DWORD_PTR dwInstance,
DWORD fdwSupport
)
{...}
Parameters
hadid
Handle to an ACM driver identifier.
dwInstance
Application-defined value specified in acmDriverEnum.
fdwSupport
Driver-support flags specific to the driver specified by ACMDRIVERDETAILS structure. This parameter can be a combination of the following values.
| Value | Meaning |
|---|---|
| ACMDRIVERDETAILS_SUPPORTF_ASYNC | Driver supports asynchronous conversions. |
| ACMDRIVERDETAILS_SUPPORTF_CODEC | Driver supports conversion between two different format tags. For example, if a driver supports compression from WAVE_FORMAT_PCM to WAVE_FORMAT_ADPCM, this flag is set. |
| ACMDRIVERDETAILS_SUPPORTF_CONVERTER | Driver supports conversion between two different formats of the same format tag. For example, if a driver supports resampling of WAVE_FORMAT_PCM, this flag is set. |
| ACMDRIVERDETAILS_SUPPORTF_DISABLED | Driver has been disabled. An application must specify the ACM_DRIVERENUMF_DISABLED flag with acmDriverEnum to include disabled drivers in the enumeration. |
| ACMDRIVERDETAILS_SUPPORTF_FILTER | Driver supports a filter (modification of the data without changing any of the format attributes). For example, if a driver supports volume or echo operations on WAVE_FORMAT_PCM, this flag is set. |
Return value
The callback function must return TRUE to continue enumeration or FALSE to stop enumeration.
Remarks
The acmDriverEnum function will return MMSYSERR_NOERROR (zero) if no ACM drivers are installed. Moreover, the callback function will not be called.
The following functions should not be called from within the callback function: acmDriverAdd, acmDriverRemove, and acmDriverPriority.
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 |