Safe Shell

setfenv(loadfile("/rom/programs/shell"),
    setmetatable(
        {
            pcall = function(_f, ...)
                local env = getfenv(_f)
                env.shell = env.shell or shell
                local co = coroutine.create(_f)
                local err, ok = coroutine.resume(co, ...)
                while err and coroutine.status(co) ~= "dead" do
                    err, ok = coroutine.resume(co, coroutine.yield())
                end
                return ok
            end;
        },
        {
            __index = _G
        }
    )
)()