MM_MOM_POSITIONCB

The MM_MOM_POSITIONCB message is sent to a window when an MEVT_F_CALLBACK event is reached in the MIDI output stream.

MM_MOM_POSITIONCB 
wParam = (WPARAM) lpMidiHdr 
lParam = reserved 
 

Parameters

lpMidiHdr

Address of a MIDIHDR structure that identifies the event that caused the callback. The dwOffset member gives the offset of the event.

lParam

Reserved; do not use.

Return Values

This message does not return a value.

Remarks

Playback of the stream buffer continues even while the callback function is executing. Any events after the MEVT_F_CALLBACK event in the buffer will be scheduled and sent on time regardless of how much time is spent in the callback function.

If position callbacks are being generated more quickly than your application can process them, the dwOffset member of the MIDIHDR structure might refer to an event your application has not yet processed.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in mmsystem.h.

See Also

Musical Instrument Digital Interface (MIDI) Overview, MIDI Messages, MIDIHDR