Re: [Discuss-gnuradio] problems with python blocks [attn: jblum]

[Josh Blum]

On 12/12/2011 05:10 PM, Paul Miller wrote:
> 
> On Wed, Dec 7, 2011 at 2:03 PM, Josh Blum <address@hidden> wrote:
>> I cant say yet as to why, but at least its reproducible.
> 
> I spent a few hours source diving today and gdb-stepping.  I
> could not figure it out, but I did find that it's broken in every
> minor release after 2.0.1 (2.0.2, 3 and 4).
> 

Its weird that feval works ok, I tried for a bit, but I couldnt figure
out what was different about my blocks. This will take more effort to
figure out if thats possible, but I do think its a bug in swig.

> I finally gave up and just left 2.0.1 installed.  Now I can at
> least work in my cool block.  But my boring test block still
> doesn't work.  It nolonger sagfaults, which is nice, but it seems
> to loop forever.  I've been pouring over the docs (such as they
> are) and I can't see any obvious reason why it should loop
> infinitely like it does.  I noticed none of your QA uses
> basic_block.  I'd give up and use sync_block, but I expect you
> want to know about these problems.
> 
> On the other hand, I still find it rather likely I'm just doing
> something wrong.  The verbosity code long cuts are due to the
> fact that I've been debugging for a while, but this is what I'm
> seeing infinitely loop right now:
> 
> 

Try retuning -1 when your block no longer gets any samples. Basically,
it has no condition in which to exit, so it runs forever. Most blocks
are like this, which is why you dont use run(), but rather
start()/stop() for the continuous processing case.