Protocol Reference

Table of Contents
Client to server messages
Server to client messages
Game message in both directions

As of protocol version 2, the following messages are defined.

Four types of data are exchanged between the client and the server:

char: a 1-byte signed char.
int: a 4-byte signed integer in network byte order.
string: a multibyte null-terminated string preceded by its length (including null-termination) as an integer.
varying: data format depends on the message type.

Interactions take one of three forms: server messages, client requests, and server responses. Each interaction is prefaced by an opcode identifying it (some interactions consist solely of the opcode). The opcode (stored as an enumerated value) is sent as an int. A minor opcode sometimes follows it.

Client to server messages

These messages are sent by the client to the server. This section does not cover responses to messages generated by the server, since those are valid in both direction. Instead, messages generated by the client on its own are documented here.