apt.conf

   1 DPkg::Pre-Install-Pkgs { "if [ -x /usr/bin/etckeeper ]; then etckeeper pre-install; fi"; };
   2 DPkg::Post-Invoke      { "if [ -x /usr/bin/etckeeper ]; then etckeeper post-install; fi"; };
   3
   4 RPM::Pre-Install-Pkgs { "if [ -x /usr/bin/etckeeper ]; then etckeeper pre-install; fi"; };
   5 RPM::Post-Invoke      { "if [ -x /usr/bin/etckeeper ]; then etckeeper post-install; fi"; };