Update lsof.md

jaywcjlove · web-flow · commit 7afb5c638b84 · 2018-06-21T21:52:09.000+08:00
diff --git a/command/lsof.md b/command/lsof.md
@@ -133,4 +133,10 @@ events/1      7 root  cwd       DIR                8,2     4096          2 /
 lsof -p $pid
 ```
 
-<!-- Linux命令行搜索引擎：https://jaywcjlove.github.io/linux-command/ -->
+获取端口对应的进程ID=>pid
+
+```
+lsof -i:9981 -P -t -sTCP:LISTEN
+```
+
+<!-- Linux命令行搜索引擎：https://jaywcjlove.github.io/linux-command/ -->
