[Discuss-gnuradio] Is there a way to know whether more input data will become available?

[Markus Wirsing]

Hello,

I have the following problem:

I wrote a block that does some processing and needs to look ahead in the
data for a certain amount.
Therefore the work function of the sync_block will return 0 if the
current amount of data is insufficient.

This works fine if the program is running infinitely.
However, when using a head block and running to completion,
it can occur that there is no more data available, which leads to the
scheduler infinitely trying again to call the work function, which then
returns 0.
Can this be detected by the block, so that the block can empty the input
buffer and the program can complete?

Or is there another good way to solve this problem?
I feel like this should be a common problem, but I haven't found a good
solution.

Thank you in advance for any hints on how to solve this.