Screen Poller
Purpose
Poll monitor number, if not equal with above, refreash screen infos.
Because sometimes plug or unplug VGA no event emitted by kernel.
Implementation
The number of monitors via calling libdrm drmModeGetResources
The refrash operation via calling libxrandr XRRGetScreenResources
Install
Depends: libx11, libdrm, libxrandr
make && sudo make install
It will autostart after user logined.