in src/libguac/protocol.c [1220:1251]
int guac_protocol_send_transfer(guac_socket* socket,
const guac_layer* srcl, int srcx, int srcy, int w, int h,
guac_transfer_function fn, const guac_layer* dstl, int dstx, int dsty) {
int ret_val;
guac_socket_instruction_begin(socket);
ret_val =
guac_socket_write_string(socket, "8.transfer,")
|| __guac_socket_write_length_int(socket, srcl->index)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, srcx)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, srcy)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, w)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, h)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, fn)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, dstl->index)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, dstx)
|| guac_socket_write_string(socket, ",")
|| __guac_socket_write_length_int(socket, dsty)
|| guac_socket_write_string(socket, ";");
guac_socket_instruction_end(socket);
return ret_val;
}