The in-process agent is able to communicate with both gdb and GDBserver (see In-Process Agent). This section documents the protocol used for communications between gdb or GDBserver and the IPA. In general, gdb or GDBserver sends commands (see IPA Protocol Commands) and data to in-process agent, and then in-process agent replies back with the return result of the command, or some other information. The data sent to in-process agent is composed of primitive data types, such as 4-byte or 8-byte type, and composite types, which are called objects (see IPA Protocol Objects).