* to modify the image).
* <p>
* This is equivalent to the qemu parameter "-drive
- * file=filename,cache=off".
+ * file=filename,cache=off,if=virtio".
* <p>
* Note that this call checks for the existence of
* "filename". This stops you from specifying other types
* although qemu can support this.
* <p>
* This is equivalent to the qemu parameter "-drive
- * file=filename,snapshot=on".
+ * file=filename,snapshot=on,if=virtio".
* <p>
* Note that this call checks for the existence of
* "filename". This stops you from specifying other types
* "-rwxr-xr-x", and 002 which creates new files with
* permissions like "-rw-rw-r--" or "-rwxrwxr-x".
* <p>
+ * The default umask is 022. This is important because it
+ * means that directories and device nodes will be created
+ * with 0644 or 0755 mode even if you specify 0777.
+ * <p>
* See also umask(2), "g.mknod", "g.mkdir".
* <p>
* This call returns the previous umask.