The midiOutGetDevCaps function queries a specified MIDI output device to determine its capabilities.

MMRESULT midiOutGetDevCaps(
  UINT_PTR      uDeviceID,      
  LPMIDIOUTCAPS lpMidiOutCaps,  
  UINT          cbMidiOutCaps   



Identifier of the MIDI output device. The device identifier specified by this parameter varies from zero to one less than the number of devices present. The MIDI_MAPPER constant is also a valid device identifier.

This parameter can also be a properly cast device handle.


Pointer to a MIDIOUTCAPS structure. This structure is filled with information about the capabilities of the device.


Size, in bytes, of the MIDIOUTCAPS structure. Only cbMidiOutCaps bytes (or less) of information is copied to the location pointed to by lpMidiOutCaps. If cbMidiOutCaps is zero, nothing is copied, and the function returns MMSYSERR_NOERROR.

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 specified pointer or structure is invalid.
MMSYSERR_NODRIVER The driver is not installed.
MMSYSERR_NOMEM The system is unable to load mapper string description.


To determine the number of MIDI output devices present in the system, use the midiOutGetNumDevs function.


**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Mmsystem.h; include Windows.h.
**  Library:** Use Winmm.lib.
**  Unicode:** Implemented as Unicode and ANSI versions on Windows NT/2000/XP.

See Also

Musical Instrument Digital Interface (MIDI), MIDI Functions, MIDIOUTCAPS, midiOutGetNumDevs