another app is currently holding the yum lock;waiting for it to exit...

用yum时，出现以下情况：

another app is currently holding the yum lock;waiting for it to exit...

可以通过强制关掉yum进程：

kill无效。强制删除pid文件。

#rm -f /var/run/yum.pid

然后就可以使用yum了。