Re: [Discuss-gnuradio] Problem feeding garbage to GNU Radio

[Johnathan Corgan]

On Sat, 2008-10-11 at 13:04 -0400, Philip Balister wrote:

> Right now I'm working through figuring out how many python modules are
> needed to run the flow graph, if I have a chance I'll try and get a
> stack trace. I'm assuming you gsb python and run the flow graph? Arg,
> how do I get the python interpreter to load and run top_block.py .....

Add a few lines at the very beginning of your script:

import os
print "pid =", os.getpid()
raw_input("Press enter to continue")

Run your script as you would normally; it will pause here.

In another window, run 'gdb -p XXXX' where XXXX is the pid printed by
your Python script.  When it gets to its prompt, enter 'cont'.

Now you can press Enter in your Python script and the whole thing will
be running under the control of gdb.  When you get the segfault, you
won't see it in the terminal with Python running; it will just appear to
freeze.  But if you go back to the terminal running gdb, you will see it
has taken over and will have printed some information about the type and
location of the segfault.

You can use the 'bt' command to print the current execution stack in the
offending thread.