[PATCH] make udev user callable to query the database

Here is a slightly better version that prints the usage if a unknown option is given:
  kay@pim:~/src/udev.kay$ ./udev -x
  ./udev: invalid option -- x
  Usage: [-qrVh]
    -q arg     query database
    -r         print udev root
    -V         print udev version
    -h         print this help text


> Here is a patch that makes it possible to call udev with options on the command line.
> Valid options are for now:
>
> -V for the udev version:
>     kay@pim:~/src/udev.kay$ ./udev -V
>     udev, version 011_bk
>
> -r for the udev root:
>     kay@pim:~/src/udev.kay$ ./udev -r
>     /udev/
>
> -q to query the database with the sysfs path for the name of the node:
>     kay@pim:~/src/udev.kay$ ./udev -q /class/video4linux/video0
>     test/video/webcam0

1 files changed, 1 insertions, 0 deletions

diff --git a/udevdb.h b/udevdb.h
index d6c58ae766..f36a9ca799 100644
--- a/udevdb.h
+++ b/udevdb.h
@@ -11,6 +11,7 @@
 /* function prototypes */
 extern void udevdb_exit(void);
 extern int udevdb_init(int init_flag);
+extern int udevdb_open_ro(void);
 
 extern int udevdb_add_dev(const char *path, const struct udevice *dev);
 extern int udevdb_get_dev(const char *path, struct udevice *dev);