MODM_PROPERTIES function

WINMM sends the MODM_PROPERTIES message to the modMessage function of a MIDI output driver to change the properties of the output stream.

Syntax

DWORD modMessage(
   UINT      uDeviceID,
   UINT      uMsg,
   DWORD_PTR dwUser,
   DWORD_PTR dwParam1,
   DWORD_PTR dwParam2
);

Parameters

• uDeviceID
  Specifies the ID of the target device. Device IDs are sequential and have with an initial value of zero and a final value that is equal to one less than the number of devices that the driver supports.

• uMsg
  WINMM sets this parameter to MODM_PROPERTIES when it calls modMessage to process this message.

• dwUser
  Use this parameter to return instance data to the driver. Drivers that support multiple clients can use this instance data to track the client that is associated with the message.

• dwParam1
  Contains a far pointer to a structure that contains information about the stream.

• dwParam2
  Contains flags that specify the operation and property. The property flags are set in the lower 30 bits of the value. These property bits are combined with one of the flags in the following table, by using the logical OR operator.

  Flag	Meaning
  MIDIPROP_SET	Tells the driver to set the specified property.
  MIDIPROP_GET	Tells the driver to read (get) the specified property.

Return value

The modMessage function returns MMSYSERR_NOERROR if the operation is successful. Otherwise, it returns one of the error messages in the following table.

Return code	Description
MMSYSERR_NOTENABLED	The driver failed to load or initialize.
MMSYSERR_INVALIDPARAM	The specified property or property value is invalid.

Remarks

For more information about the properties of a MIDI data stream, see midiStreamProperties. Also see MIDIPROPTEMPO.

Requirements

Target platform	Desktop
Version	Available in Windows XP and later Windows operating systems.
Header	Mmddk.h (include Mmddk.h, Mmsystem.h, or Windows.h)

See also

modMessage

midiStreamProperties

MIDIPROPTIMEDIV

MIDIPROPTEMPO