[getuid] add usb_id

Well, this is useful for testing with usb keys

diff --git a/getuid/usb_id b/getuid/usb_id
new file mode 100755 (executable)
index 0000000..800e471
--- /dev/null
+++ b/getuid/usb_id
@@ -0,0 +1,6 @@
+#!/bin/sh
+#
+# copy in /bin and add this line to a device block in multipath.conf :
+# getuid_callout          "/bin/usb_id %n"
+#
+cd /sys/block/$1 && cd $(ls -l device|cut -d">" -f2) && cd ../../../.. && cat serial