anchor.diff:            -drive file=$NIX_DISK_IMAGE,if=virtio,boot=on \
             -kernel ${config.system.build.toplevel}/kernel \
             -initrd ${config.system.build.toplevel}/initrd \
  +          ${qemuGraphics} \
             $QEMU_OPTS \
  -          -append "$(cat ${config.system.build.toplevel}/kernel-params) init=${config.system.build.bootStage2} systemConfig=${config.system.build.toplevel} $QEMU_KERNEL_PARAMS"
  +          -append "$(cat ${config.system.build.toplevel}/kernel-params) init=${config.system.build.bootStage2} systemConfig=${config.system.build.toplevel} ${kernelConsole} $QEMU_KERNEL_PARAMS"
       '';
   
   in
  
positive.code:             exist.
            '';
        };
  
    };
  
  
    # Shell script to start the VM.
    startVM =
  
negative.code:   services.xserver.defaultDepth = mkOverride 50 {} 0;
    services.xserver.resolutions = mkOverride 50 {} [];
  
    services.mingetty.ttys = ttys ++ optional (!cfg.graphics) "ttyS0";
  
    # Wireless won't work in the VM.
    networking.enableWLAN = mkOverride 50 {} false;
  }
  