Re: Adaptation of Federico La Roccas ISDB-T blocks for DVB-T

[Vasil Velichkov]

Hi Ralf,

On 10/12/2021 11.52, Ralf Gorholt wrote:
> Unfortunately, when I deactivate the original flowgraph, it does no
> longer work and I get a -11 return code. 

The "-11" value means that you got a segmentation fault and the process was 
kill with signal 11 (SIGSEGV)

https://docs.python.org/3.8/library/subprocess.html#subprocess.CalledProcessError.returncode
https://www.man7.org/linux/man-pages/man7/signal.7.html

In my opinion the easiest way to debug segfaults is to run the flowgraph under 
gdb and valgrind. Open your flowgraph in the gnuradio-companion and then 
Generate (F5) but do not Execute (F6). The open a terminal, go where the 
flowgraph python (.py) file was generated and execute

 gdb -ex run --args /usr/bin/python3 test.py

and then when it stops execute `bt` command in the gdb's shell and provide the 
full output. To run it under valgrind execute

 valgrind --tool=memcheck /usr/bin/python3 test.py

Adjust the path to your python interpreter and its version if needed.

Regards,
Vasil