Update README.md

@@ -8,7 +8,7 @@ can be used as origin server, or rtmp-server for encoder.
 2. high-performance: single-thread, async socket, event/st-thread driven.
 2. high-performance: single-thread, async socket, event/st-thread driven.
 3. support origin and edge mode.
 3. support origin and edge mode.
 4. only for live streaming.
 4. only for live streaming.
-5. donot support vhost, __defaultVhost__ only.
+5. donot support vhost, \_\_defaultVhost\_\_ only.
 6. single process, no multiple processes yet.
 6. single process, no multiple processes yet.
 
 
 Winlin
 Winlin