问题描述：
This is the message displayed in my terminal screen when I typed
sudo ap-hotspot start
Another process is already running
Which process is running and how do I stop it?
解决方法：
I found this solution
sudo rm /tmp/hotspot.pid
this will delete the process id created temporarily and no more the error is displayed. This worked in my case.
Ubuntu 15.04编译JDK7 HotSpot虚拟机：http://www.linuxdiyf.com/linux/12528.html