CLIENT_VERSION
together with the maplist request to the version server.
https://github.com/teeworlds/teeworlds/blob/26d24ec061d44e6084b2d77a9b8a0a48e354eba6/src/game/version.h#L9
The version server can send different map versions for different client versions. The default version is 0.7.x if the request packet does not contain...io_read_all
io_read_all_str
is supposed to be used for zero-terminated strings instead.
io_read_all_str