The final checklist item lets the MCI parser know that you have a custom command table. Do this by making the following call in your driver's DRV_LOAD message handler:
wTableEntry = mciLoadCommandResource (hInstance, "pioneer", 0);
This example loads the resource named “pioneer,” registers it with MCI, and returns a handle to that table.
If you have created a custom command table, your device driver must free the table when your device driver terminates. To free the table, include the following call in your device driver's DRV_FREE message handler:
fResult = mciFreeCommandResource (wTableEntry);
Use the table index number returned from mciLoadCommandResource as the argument to this function. This function returns TRUE if the table index number is valid.