解决E:Unable to lock /var/lib/apt/lists问题

1、在sudo apt-get update时，报E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily unavailable)不能获得锁定。

示例如下：

$ sudo apt-get update

E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily unavailable)

E: Unable to lock directory /var/lib/apt/lists/

2、在/var/lib/apt/lists下有一个残留的lock文件是这个问题的原因。

$ sudo rm /var/lib/apt/lists/lock