function Linemode:mtime()
    local time = math.floor(self._file.cha.mtime or 0)
    if time == 0 then
        return ""
    elseif os.date("%Y", time) == os.date("%Y") then
        return os.date("%d %b %H:%M", time)
    else
        return os.date("%d %b %y", time)
    end
end