anchor.diff:          chown root /var/gvpe
           chmod 700 /var/gvpe
           cp ${finalConfig} /var/gvpe/gvpe.conf
  -	cp ${ifupScript} /var/gvpe/if-up
  +        cp ${ifupScript} /var/gvpe/if-up
         '';
   
         inherit exec;
  
positive.code: 
  let 
    inherit (pkgs.lib) mkOption mkIf;
    cfg = config.services.gvpe;
    finalConfig = if cfg.configFile != null then 
      cfg.configFile
    else if cfg.configText != null then
  
negative.code:     '';
      executable = true;
    });
  
    exec = "${pkgs.gvpe}/sbin/gvpe -c /var/gvpe -D ${cfg.nodename} "
      + " ${cfg.nodename}.pid-file=/var/gvpe/gvpe.pid"
      + " ${cfg.nodename}.if-up=if-up"
      + " &> /var/log/gvpe";
  
    inherit (cfg) startOn stopOn;
  in
  
  