This was a question asked by Rob a couple of days ago. He wanted to know if there was a way to disable the pop up message, which appears when you close a Terminal window. This message usually pops up when you have a Unix program such as ssh running and it warns you when you are about to close it. Its quite useful if you tend to close windows a lot but for Unix power users it can get in the way.
It is really simple to remove the warning. In Terminal go to Preferences > Settings > Shell. You will have plenty of options here. The one you want to look for it at the bottom under “Prompt Before Closing”. This controls the prompt as shown in the image above. You can Always, so it will always be shown. Never, which is the option you want to remove the warning every time. The final option you can use to customize when it comes up, for instance you can warn when it comes up when you use ssh and you can disable it at other times.
A very simple tip which I hope you will find useful.