if gate_travel==nil then
dofile(scriptpath .. "/gates.lua")
end
buildings = {}
function portal_exchange(b1, param)
b2 = buildings[param]
if buildings[param] == nil then
buildings[param] = b1
else
u1 = gate_units(b1, 100)
u2 = gate_units(b2, 100)
gate_travel(b1, u2)
gate_travel(b2, u1)
return 1