Removing selection rectangle

[Maelstrom]

Like the subject says, I need to remove the selection rectangle around units. Unfortunately, I cant just copy trepans method of doing it. The error is:

Code: Select all

LUACOB-MAIN  (GADGETS)
LUACOB-DRAW  (GADGETS)
LUARULES-MAIN  (GADGETS)
error = 2, LuaRules/draw.lua, error = 2, LuaRules/gadgets.lua, [string "LuaRules/Gadgets/gui_roundselection.lua"]:49: attempt to index global 'io' (a nil value)

The code is:

Code: Select all

function SetupCommandColors(state)
  local alpha = state and 1 or 0
  local f = io.open('cmdcolors.tmp', 'w+')      <---- line 49
  if (f) then
    f:write('unitBox  0 1 0 ' .. alpha)
    f:close()
    Spring.SendCommands({'cmdcolors cmdcolors.tmp'})
  end
  os.remove('cmdcolors.tmp')
end

Either I need another way of removing the selection rectangles, or how to fix the error. Any ideas?

Thanks