Amount Display

items = {{"Stone", 1}, {"Dirt", 3}, {"Cobble", 4}}

function split(pString, pPattern) --("A_Small_Dog", "_")
  local Table = {}
  local fpat = "(.-)" .. pPattern
  local last_end = 1
  local s, e, cap = pString:find(fpat, 1)
  while s do
    if s ~= 1 or cap ~= "" then
      table.insert(Table, cap)
    end
    last_end = e + 1
    s, e, cap = pString:find(fpat, last_end)
  end
  if last_end <= #pString then
    cap = pString:sub(last_end)
    table.insert(Table, cap)
  end
  return Table
end

function getReply(uuid)
  id, message = rednet.receive()
  m = split(message, " ")
  if m[1] == "inv" then
    if m[2] == "replyAmount" then
      if tonumber(m[3]) == tonumber(uuid) then
        return m[4]
      end
    end
  end
  return nil
end

mon = peripheral.wrap("left")
mon.clear()

rednet.open("back")

while true do
  for i=1, #items do
    rednet.broadcast("inv getAmount " ..items[i][2])
    amount = nil
    while amount == nil do
      amount = getReply(items[i][2])
    end

    mon.setCursorPos(1, i)
    mon.write(items[i][1] ..": " ..amount)
  end
  sleep(30)
end