GNU Radio C++ Block Appends Zero Entries

GNU Radio
1

Hi,

I have written a simple ‘general’ C++ block that takes some complex
values from a file source and outputs ints to a file as binary.

I find that it adds a ‘0’ after every time the block is called, so if I
have 10 input values in the file, then it runs using the first 8,
outputs 8 values correctly and adds a 0, then runs using the last 2,
outputs 2 values correctly and then adds a 0.

If anyone is interested or has experienced something similar, I will
provide some code!

David

2

Hi,

I have simplified my code; as below and attached. I include a simple
flow graph too. Lots of 0’s are appended to the output file? I must be
making a silly mistake?!

Thanks for any help!

Regards,

David

/*
 * The private constructor
 */
cip_vcic_impl::cip_vcic_impl(int v_len, int r_max, int l_max)
  : gr::block("cip_vcic",
          gr::io_signature::make(1, 1, sizeof(gr_complex)),
          gr::io_signature::make(1, 1, sizeof(gr_complex)))
{}

/*
 * Our virtual destructor.
 */
cip_vcic_impl::~cip_vcic_impl()
{
}

void
cip_vcic_impl::forecast (int noutput_items, gr_vector_int

&ninput_items_required)
{
ninput_items_required[0] = noutput_items;
}

int
cip_vcic_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];


    // Copy input to output
    for(int item_idx = 0; item_idx < ninput_items[0]; item_idx++)
    {
        memcpy((void *) &out[item_idx], (void *) &in[item_idx],

sizeof(gr_complex));
produce(0, 1);
}

    // Tell runtime system how many input items we consumed on
    // each input stream.
    consume_each (noutput_items);

    // Tell runtime system how many output items we produced.
    return noutput_items;
}
3

p.s. clearly this takes in complex and puts out complex (not ints like
my original code/explanation).