[[license text="""
Copyright © 2007 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the
terms of the GNU Free Documentation License, Version 1.2 or any later version
published by the Free Software Foundation; with no Invariant Sections, no
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Sometimes using [[GDB]] on a system server can result in a [[deadlock]].  You
can however still use GDB by using the [`set
noninvasive`](http://sourceware.org/gdb/current/onlinedocs/gdb_19.html#Hurd%20Native)
option.  This indicates to GDB to not stop the program but allows you to
nevertheless examine its state.  Thus, you can get back traces and value of
variables (and watch them change underneath you).