yum -y install wget
Loaded plugins: fastestmirror, refresh-packagekit, security
Existing lock /var/run/yum.pid: another copy is running as pid 25960.
Another app is currently holding the yum lock; waiting for it to exit...
可能是系统自动升级正在运行，yum在锁定状态中。
已经有一个yum进程在运行了，使用kill杀死它
kill -9 25960
kill对付不了它：
可以通过强制关掉yum进程：
#rm -f /var/run/yum.pid
然后就可以使用yum了。
yum提示Another app is currently holding the yum lock
原文：https://blog.51cto.com/14243230/2480346