Re: [Discuss-gnuradio] Can't stop the top_block which contain transmit_path with GNU Radio version 11001

[Eric Blossom]

On Fri, May 15, 2009 at 05:51:30PM -0700, Ling Huang wrote:
> 
> sorry for attaching this again. 
> I use UBUNTU 9.04 + gnuradio 11001 and UBUNTU 8.10 +gnuradio 10853 got the
> same problem.
> 
> I modify the gnuradio-examples/python/digital codes for some experiences. In
> one case I want to stop the running flow graph(top block), and then to start
> a new connect. I do it well in stop the receive_path connect. But I just
> can't stop the top block contain a transmit_path. If I stop the top block,
> and wait, it hang in the tb.wait. 
> I seem not express well. To make it simple let's see: 
> class my_topblock(gr.top_block) 
>     def __init__(self): 
>          self.trans=transmit_path(...) 
>          self.connect(self.trans) 
> .... 
> 
> tb.start() 
> tb.stop() 
> tb.wait() # IT HANG IN HERE 
> ... 
> tb.start() 
> 
> I made a simple test code to test stopping the top block , please test it to
> see what's the problem. 

Some block is most likely blocked in a system call.  I'm guessing that
the transmit path is hung in gr.message_source waiting for a message
that's never coming.  To get it to stop, send it a message with
type=1.  The message source will indicate that it is done and the flow
graph will terminate.

Eric