1、当大家用linux的yum时，是不是经常会遇到下面的情况
Loaded plugins: fastestmirror
Existing lock /var/run/yum.pid: another copy is running as pid 3404.
Another app is currently holding the yum lock; waiting for it to exit...
The other application is: yum
Memory : 41 M RSS (253 MB VSZ)
Started: Wed Apr 11 07:03:37 2012 - 00:25 ago
State : Sleeping, pid: 3404
没关系，两条语句就可以搞定它。
2、[root@centos5 ~]# rm -r /var/run/yum.pid
rm：是否删除 一般文件 “/var/run/yum.pid”? y
[root@centos5 ~]# /sbin/service yum-updatesd restart
停止 yum-updatesd： [确定]
启动 yum-updatesd： [确定]
3、[root@centos5 ~]# yum install gcc*
搞定！！！