Chatbox Command Spy

local function fwrite(n, c)
    local f = fs.open(n, "w")
    f.write(c)
    f.close()
end

local function fread(n)
    local f = fs.open(n, "r")
    local out = f.readAll()
    f.close()
    return out
end

local file = "gccs"
local optins = textutils.unserialise(fread(file))

local function save()
    fwrite(file, textutils.serialise(optins))
end

local chatbox = peripheral.find "chat_box"

while true do
    local _, sender, type, arguments = os.pullEvent "command"
    if type == "gccs-optin" then
        optins[sender] = true
        save()
    elseif type == "gccs-optout" then
        optins[sender] = nil
        save()
    end
    local text = sender .. ": \\" .. type .. " " .. table.concat(arguments, " ")

    for user in pairs(optins) do
        chatbox.tell(user, text, "\167bG\167aCCS\1677", "\1678")
    end
end