midiStreamOpen
The midiStreamOpen function opens a MIDI stream for output. By default, the device is opened in paused mode. The stream handle retrieved by this function must be used in all subsequent references to the stream.
MMRESULT midiStreamOpen(
LPHMIDISTRM lphStream,
LPUINT puDeviceID,
DWORD cMidi,
DWORD dwCallback,
DWORD dwInstance,
DWORD fdwOpen
);
Parameters
-
lphStream
-
Address of a variable to contain the stream handle when the function returns.
-
puDeviceID
-
Address of a device identifier. The device is opened on behalf of the stream and closed again when the stream is closed.
-
cMidi
-
Reserved; must be 1.
-
dwCallback
-
Address of a callback function, an event handle, a thread identifier, or a handle of a window or thread called during MIDI playback to process messages related to the progress of the playback. If no callback mechanism is desired, specify NULL for this parameter.
-
dwInstance
-
Application-specific instance data that is returned to the application with every callback function.
-
fdwOpen
-
Callback flag for opening the device. One of the following callback flags must be specified:
-
CALLBACK_EVENT
-
The dwCallback parameter is an event handle. This callback mechanism is for output only.
-
CALLBACK_FUNCTION
-
The dwCallback parameter is a callback procedure address.
-
CALLBACK_NULL
-
There is no callback mechanism. This is the default setting.
-
CALLBACK_THREAD
-
The dwCallback parameter is a thread identifier.
-
CALLBACK_WINDOW
-
The dwCallback parameter is a window handle.
Return Values
Returns MMSYSERR_NOERROR if successful or an error otherwise. Possible error values include the following:
Value |
Description |
MMSYSERR_BADDEVICEID |
The specified device identifier is out of range. |
MMSYSERR_INVALPARAM |
The given handle or flags parameter is invalid. |
MMSYSERR_NOMEM |
The system is unable to allocate or lock memory. |
QuickInfo
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in mmsystem.h.
Import Library: Use winmm.lib.
See Also
Musical Instrument Digital Interface (MIDI) Overview, MIDI Functions