+if (process.argv.length >= 3) {
+ json_filename = process.argv[2];
+}
+
+// TCP port to listen on.
+var port = 5000;
+if (process.argv.length >= 4) {
+ port = parseInt(process.argv[3]);
+}
+
+// If set to 1, we are already processing a JSON update and should not
+// start a new one. If set to 2, we are _also_ having one in the queue.
+var json_lock = 0;