pi@raspberrypi ~ $ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages have been kept back:
  fake-hwclock gir1.2-gtk-3.0 gir1.2-pango-1.0 libfm-data libgail-3-0 libgcc1
  libgfortran3 libgomp1 libgtk-3-0 libgtk-3-bin libgtk-3-common
  libjavascriptcoregtk-3.0-0 libpango1.0-0 libstdc++6 libwebkitgtk-3.0-0
  lxpanel omxplayer pcmanfm zenity zenity-common
0 upgraded, 0 newly installed, 0 to remove and 20 not upgraded.