How can you restart a flow graph after a head block kills it? For example, I want to do something like the following: tb.start() tb.wait() # head block will terminate ... do some reconfiguration ... tb.start() However, I get a seg fault if I ever try to call tb.start() after the head block returns. I take it a flow graph isn't reusable after a head block terminates? If I remove the head block: tb.start() tb.stop() tb.wait() tb.start() Works just fine. Could someone explain what is going on or point me to the documentation (having a hard to finding anything useful in the documentation).
on 2014-01-29 00:00
on 2014-01-29 00:24
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Ken, since segfaults are never desirable, we should look into the issue. Generally, I'd say that flowgraphs are not really meant for restarting if not special precautions were made. Many blocks are stateful, meaning that it does matter if you're the first sample to be processed or the xth one; this is especially the case for the head block. A flowgraph really just represents the connections between the blocks - - the blocks are created prior to connecting and continue to exist after the flowgraph stopped. So, unless starting a block anew resets its state, there is no guarantee that things will work as in the first call to start. However, head should not crash; I will look into that tomorrow morning. Could you please provide a minimal flowgraph example, and your GR version as well as a little information on your platform (OS, architecture)? Greetings Marcus On 28.01.2014 23:58, Ken Adams wrote: > > mailing list Discussemail@example.com > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJS6Du8AAoJEAFxB7BbsDrLcyUH/0ba9S7nILMgYhHXb8cf/X4N Rh1kIMatQG8eV87+dVR0FFVXrEABFlrGenFX+/hxG/yhuge7D81OZHpC+fho8yjh Rfb8ibiRQ9FJO9NPHiKE6SiN5F32kGFzub39CqcoN4JL3b9OltExKoqs8VAJ3gRr I/hugN4vPVlWugJr11TAEhBqqsU9eJFFaKs5y0wQ3FErGl3huIdnWv7WHBblvc/s /t7hKDMb7P3iV0mKmlOfeGDvIMX8XNUN/e23NIwQ5PPhgW3t5HGVWZmX8ytdCuOZ f/tjhH2bxYMrUak2MzGu3zE5BAVjpE9LRnykMIkreDUSRiXtsttPCDbeaEzNIwY= =f9xC -----END PGP SIGNATURE-----