anchor.diff:  FROM ubuntu:14.04
   MAINTAINER Stefan Schwetschke "stefan@schwetschke.de"
   
  -ENV REFRESHED_APT_AT 2015-01-15
  -
  -RUN apt-get update -y
  -RUN apt-get upgrade -y
  +ENV REFRESHED_APT_AT 2015-01-18
   
   # Set locale to UTF-8 to fix the locale warnings
   RUN localedef -v -c -i en_US -f UTF-8 en_US.UTF-8 || :
  
positive.code: ENV DEBIAN_FRONTEND noninteractive
  
  # Installing the environment required: xserver, xdm, flux box, roc-filer and ssh
  RUN apt-get install -y lxde-core lxterminal xvfb x11vnc sudo
  
  
  # Fix problems with Upstart and DBus inside a docker container.
  RUN dpkg-divert --local --rename --add /sbin/initctl && ln -sf /bin/true /sbin/initctl
  
  # Install some basic packages
  RUN apt-get install -y firefox xterm
  
  # Copy the files into the container
  ADD . /x11-src
  RUN chmod -R a=rX /x11-src
  
  # Clean up apt-get
  RUN apt-get clean
  
  # Local user, may be overwritten by dependent build
  ENV X11_USER xclient
  
negative.code: # Resolution and color depth of simulated display
  ENV RESOLUTION 1280x1024x16
  
  VOLUME /home
  EXPOSE 5900
  
  # Start x11vnc
  