API

local oldRednet = rednet
local oldSide = false


-- shorter functions
local net = rednet
local brod = net.broadcast
local pull = os.pullEvent

function send(id, msg)
    net.send(id, msg)
end

function setMaster(ID)
    local save = fs.open(".master", "w")
    save.writeLine(tonumber(ID))
    save.close()
end

function getMaster()
    local save = fs.open(".master", "r")
    local cRead = save.readLine()
    save.close()
    return tonumber(cRead)
end

function setGlobalMessage(msg)
    local save = fs.open(".global", "w")
    save.writeLine(msg)
    save.close()
end

function getGlobalMessage()
    local save = fs.open(".global", "r")
    local cRead = save.readLine()
    save.close()
    return cRead
end

function open(side)
    oldSide = side
    rednet.open(side)
end

function close()
    rednet.close(oldSide)
end

function ping()
    setGlobalMessage(" ")
    brod("ping")
    local id, msg = rednet.receive(2)
    if msg == "pong" then
        setMaster(id)
        setGlobalMessage("Connected")
    end
    -- id, msg, dist = rednet.receive(2)
    -- print(msg)
    -- if msg == "pong" then
    --  setMaster(id)
    --  setGlobalMessage("success")
    -- end
    -- if not id then
    --  term.setTextColor(colors.red)
    --  print("Timeout")
    --  term.setTextColor(colors.white)
    -- end
end