+ necessary. The IDs themselves are 32 bits each, unsigned,
+ regardless of the pointer size. The first object in the list
+ is the object to receive the message.
+
+ Objects which live in this address space have the high bit
+ clear; remote objects have the high bit set. When sending
+ an object reference that has not been exposed to the kernel
+ before, its interface hash should exist in the newobj list.
+
+ num_segments 32-bit Number of data segments