linux 中Another app is currently holding the yum lock; waiting for it to exit...的解决方法

当我们在linux中安装一些 软件时，可能会出现这样的情况

[root@localhost home]# yum install gcc gcc-c++ kernel-devel
Loaded plugins: fastestmirror, langpacks
Existing lock /var/run/yum.pid: another copy is running as pid 12390.
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 164 M RSS (578 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 11:53 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 11:55 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 11:57 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 11:59 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:01 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:03 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:05 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:07 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:09 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:11 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:13 ago
    State  : Running, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:15 ago
    State  : Sleeping, pid: 12390
Another app is currently holding the yum lock; waiting for it to exit...
  The other application is: PackageKit
    Memory : 172 M RSS (586 MB VSZ)
    Started: Tue Feb 26 08:09:08 2019 - 12:17 ago
    State  : Sleeping, pid: 12390

解决的方法：

rm -f /var/run/yum.pid 12390

这样再重新输入yum命令就可以了。