id (USHORT)
CN_CONTEXTMENU (USHORT)
pRecord (PRECORDCORE)
If the user is using a pointing device, this RECORDCORE structure is the structure that the pointing device pointer is over. If the pointing device pointer is over white space, this field is NULL.
If the user is using the keyboard, this RECORDCORE structure is the structure that has the selection cursor.
ulReserved (ULONG)