use gst.extend.discoverer for oxinfo

bin/oxinfo

@@ -16,18 +16,18 @@ if os.path.exists(os.path.join(root, 'oxgst')):
 from oxgst import Info
 
 if __name__ == "__main__":
-
     parser = OptionParser()
     parser.add_option('-f', '--format', dest='format', help='output format: cfg, json, xml default: cfg')
     (opts, args) = parser.parse_args()
 
     if not args:
         parser.print_help()
-        sys.exit()
+        sys.exit(1)
 
     inputFile = args[0]
-    i = Info(inputFile)
-    info = i.metadata
+    if not os.path.exists(inputFile):
+        sys.exit(1)
+    info = Info(inputFile)
     if opts.format == 'xml':
         xml = ET.Element("gstinfo")
         el = ET.SubElement(xml, "path")