WaveOutFunc

The WaveOutFunc function refers to the callback function used with the waveform output device. WaveOutFunc is a place holder for the application-supplied function name. The actual name must be exported by including it in an EXPORTS statement in the DLL' s module-definition file.

Syntax

void CALLBACK WaveOutFunc(HWAVEOUT hwo, UINT uMsg, DWORD dwInstance, DWORD dwParam1, DWORD dwParam2);

At a Glance

Header file: Mmsystem.h
Component: Wavelib
Platforms: H/PC
Windows CE versions: 2.0 and later

Parameters

hwo
Handle to the waveform device associated with the callback.
uMsg
Waveform-output message.
dwInstance
User-instance data specified with waveOutOpen.
dwParam1
Parameter for the message.
dwParam2
Parameter for the message.

Remarks

Because the callback is accessed at interrupt time, it must reside in a DLL and its code segment must be specified as FIXED in the module-definition file for the DLL. Any data that the callback accesses must be in a FIXED data segment as well. The callback cannot make any system calls except for PostMessage, timeGetSystemTime, timeGetTime, timeSetEvent, timeKillEvent, midiOutShortMsg, midiOutLongMsg, and OutputDebugStr.

See Also

waveOutClose