Suspending a Thread
- Steps
Pause your application’s execution, or wait for it to hit a breakpoint.
In the Debug navigator, Control-click the desired thread.
In the contextual menu, choose Suspend Thread.

Suspend a thread to prevent it from running during your debugging session. You might suspend a thread if the thread is about to crash or if you want to prevent it from doing work that could interfere with the rest of your application.
A suspended thread does not run when you step through your code or continue execution. The debug navigator places a red status icon next to suspended threads.
To resume a thread that is currently suspended, Control-click it and select Resume Thread from the contextual menu.
The screenshot shows the Suspend Thread command in the contextual menu of the debug navigator.
© 2012 Apple Inc. All Rights Reserved. (Last updated: 2012-09-19)