Re: Options - QT GUI window size and placement

[Vasil Velichkov]

Hi Gavin,

On 14/04/2022 20.45, Gavin Jacobs wrote:
> I looked in the Python code generated by grc, and the call to saveGeometry is 
> there in closeEvent() !
> But, it is not working in my flowgraph because the flowgraph exits with:
>>>> Done (return code -11)

Return code -11 means SIGSEGV Segmentation Fault.

>From 
>https://docs.python.org/3/library/subprocess.html#subprocess.Popen.returncode

   A negative value -N indicates that the child was terminated by signal N 
(POSIX only).

and from "man 7 signal"

   SIGSEGV      11       Core    Invalid memory reference

To investigate the problem you need to run your flowgraph under gdb. In your 
terminal go in the directory where your flowgraph .py file is and execute

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

When it crash you are going to see the gdb prompt, then run

   (gdb) bt

Provide the full output if you need some more help with this.

Regards,
Vasil

> which means that the closeEvent doesn't get a chance to save the geometry.
> The -11 return codes happen if the flowgraph includes the "Soapy HackRF 
> Source" or "Soapy HackRF Sink" block.
> I think this is a bug that no one noticed.
> 
> The workaround is to disable those blocks and connect a null source or sink, 
> run the flowgraph, set the desired geometry, exit the flowgraph, then disable 
> the null and re-enable the Soapy Hackrf.
> 
> 
> 
> 
> 
> Date: Thu, 14 Apr 2022 12:59:18 +0200
> From: Marcus Müller <mueller@kit.edu>
> To: <discuss-gnuradio@gnu.org>
> Subject: Re: Options - QT GUI window size and placement
> Message-ID: <b914ffad-9578-fc07-2e53-30cbe8ff6f08@kit.edu>
> Content-Type: text/plain; charset="utf-8"; Format="flowed"
> 
> Hi Gavin,
> 
> that's not a functionality of GNU Radio itself (at least we don't have any 
> calls to the
> Qt-typical "saveGeometry"/"restoreGeometry" in our source code); it must be 
> your window
> manager?
> So, I sadly can't advise on how to achieve that, sorry.
> 
> Best,
> Marcus
> 
> On 13.04.22 18:50, Gavin Jacobs wrote:
>> I recently built a laptop with Ubuntu 20.04 and then built gnuradio 3.10.2 
>> from source. I
>> noticed that the Hackrf is now supported through the SoapySDR source/sink 
>> blocks (rather
>> than the Osmocom blocks), so I made some examples & tests of hackrf rx and 
>> tx. Works fine,
>> but I have a question.
>>
>> Previously the window that starts when the flowgraph is executed (i.e. the 
>> popup window
>> with the QT GUI widgets and instrumentation), would remember the window size 
>> and
>> placement; but now it doesn't. In 3.10.2 how do I control the window size 
>> and placement?
>>
>> Thanks,
>> Jake
> 
>