Out Of Tree module works only partially

[Ralf Gorholt]

Dear all,

I am quite new to GNU Radio and in order to see how GNU Radio blocks 
work I would like to create my own block that (for the moment) just 
copies complex data from the input to the output. This works as long as 
I copy only one number but not when I want to copy packets of numbers 
that come from the preceeding block. My block takes one parameter: 
blk_size. I would like to insert it in my DVB-T receiver flowgraph to 
analyze data (in a later step).

I had a look at the square_ff example and other blocks to see how they 
are built but I still don't see what I am doing wrong. It must be a 
silly mistake. Perhaps you can help me? Here is the code:

myblock_impl::myblock_impl(int blk_size)
        : gr::block("myblock",
                gr::io_signature::make(1, 1, blk_size * 
sizeof(gr_complex)),
                gr::io_signature::make(1, 1, blk_size * 
sizeof(gr_complex)))
    {
    }

void
    myblock_impl::forecast(int noutput_items, gr_vector_int 
&ninput_items_required)
    {
        ninput_items_required[0] = noutput_items;
    }

int
    myblock_impl::general_work(int noutput_items,
                               gr_vector_int &ninput_items,
                               gr_vector_const_void_star &input_items,
                               gr_vector_void_star &output_items)
    {
        const gr_complex *in = (const gr_complex *) input_items[0];
        gr_complex *out = (gr_complex *) output_items[0];

        for (int i = 0; i < noutput_items; i++) {
            out[i] = in[i];
        }

        consume_each(noutput_items);

        return noutput_items;
    }

And the YML file:

id: dl5eu_myblock
label: myblock
category: '[dl5eu]'

templates:
  imports: import dl5eu
  make: dl5eu.myblock(${blk_size})

parameters:
- id: blk_size
  label: Block size
  dtype: int
  default: '1'

inputs:
- label: in
  domain: stream
  dtype: complex
  vlen: ${blk_size}
  optional: '0'

outputs:
- label: out
  domain: stream
  dtype: complex
  vlen: ${blk_size}
  optional: '0'

file_format: 1

Thank you very much for your help!

Kind regards,

Ralf