Return -1 Source Block Issue

GNU Radio
1

Hi,

I’m using gnuradio for one or two months and I’m trying to implement a
flow graph with a source that has a finite time job. I have seen that
such blocks have to return -1. The problem is when the source has
finished its job the whole flow graph stops and the blocks following
the source have no time to process the whole data coming from the
source.

How can I do to let the whole data be processed by the other blocks
before stopping the flow graph?

Thank you in advance,

Antoine Dedave

2

On Mon, Dec 06, 2010 at 08:00:25PM +0100, Antoine Dedave wrote:

Hi,

I’m using gnuradio for one or two months and I’m trying to implement a flow
graph with a source that has a finite time job. I have seen that such blocks
have to return -1. The problem is when the source has finished its job the
whole flow graph stops and the blocks following the source have no time to
process the whole data coming from the source.

How can I do to let the whole data be processed by the other blocks before
stopping the flow graph?

Hi Antoine,

it seems you’re doing exactly the right thing; file sources also call -1
when reaching EOF and I’ve never had problems using them; GR should
clear out the buffers before quitting.
Perhaps you can post some more details on what you’re doing. Are you
using any blocks with histories?
For example, the following flow graph will produce N output samples:

Source -> Head, Length N -> Delay, length D -> File sink

You might expect N+D-1 samples, but the history doesn’t get flushed.
That’s normal.

MB

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