Rednet Intercept Tool

-- Rednet intercept, takes advantage of how rednet works to spy on another computer's messages
function color(xcolor)
  if term.isColor() then term.setTextColor(xcolor) end
end
color(8)
print("# Welcome to the rednet spy program")
print("# This will spy on a computer and show you")
print("   any rednet messages it receives")
color(2)
write("? Enter computer ID to spy on: ")
local id = tonumber(read())
write("? Enter spy period duration: ")
local duration = tonumber(read())
local timer = os.startTimer(duration)
local modem = peripheral.wrap("back")
color(32)
print("! Spying started")
color(1)
print("----------------------------------")
color(32)
modem.open(id)
while true do
  local e, p1, p2, p3, p4, p5 = os.pullEvent()
  if e == "modem_message" then
    print("! "..id.." recieved a message.")
    print("! From: "..p3)
    print("! Message: "..p4)
    color(1)
    print("----------------------------------")
    color(32)
  elseif e == "timer" and p1 == timer then
    break
  end
end
modem.close(id)
color(32)
print("! Spying stopped")