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Device I/O Control Codes

[The feature associated with this page, Windows Media Player SDK, is a legacy feature. It has been superseded by MediaPlayer. MediaPlayer has been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer instead of Windows Media Player SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

Windows Media Player 10 or later defines Windows Media Device Manager device I/O control codes. The following table contains the control codes and their descriptions.

I/O control code Value Description
IOCTL_WMP_METADATA_ROUND_TRIP 0x31504d57 Manages transfer of information about changes that occurred to metadata values. See Device Extensions for Accelerated Metadata Transfer.
IOCTL_WMP_DEVICE_CAN_SYNC 0x32504d57 Indicates whether a portable device supports automatic synchronization. Windows Media Player 10 or later provides no input buffer.The output buffer must return a DWORD value. A value of 1 means the device supports synchronization. A value of 0 means the device does not support automatic synchronization.
See Remarks for more information.

Remarks

These control codes are defined in wmpdevices.h.

If the device does not support IOCTL_WMP_DEVICE_CAN_SYNC, Windows Media Player 10 or later assumes the device supports automatic synchronization. Note that while this value can disallow automatic synchronization, there are additional criteria used to determine whether the device supports automatic synchronization.

Device Extensions for Accelerated Metadata Transfer

Windows Media Player