If you're having trouble with the basic functionality, I would recommend that you get that basic functionality of your code sorted out and tested in an Inline::C script before you even write SDR::RTLSDR.
That's an approach that has always worked quite well for me.

It also means that you can provide a script that shows everything you're trying to do.
It's pretty hard to work out exactly what you're doing from a few snippets.

I assume your module will link to the librtlsdr library, and I'm wondering why your XS code appears to be creating/declaring its own rtlsdr_open() when that function is already (presumably) provided by that library and the librtlsdr header.

Anyway, for an Inline::C script, you'd want something like: 
use strict;
use warnings;
use Inline C => Config =>
 #CLEAN_AFTER_BUILD => 0, #
 BUILD_NOISY => 1, # display the compilation
 inc => '-I/path/to/librtlsdr_headers',
 libs => '-L/path/to/librtsldr_library,
;

use Inline C => <<'EOC';

#include<librtlsdr_header.h>

void foo(<args>) {
  /* do something that uses librtlsdr
     and print out a success/fail message */
}

void bar(<args>) {
  /* do something else that uses librtlsdr
     and print out a success/fail message */
}

EOC

foo();
bar();

[download]
Add more functionality and complexity as you get things working.
Inline::C provides typemapping and just about everything else that XS provides. (See the Inline::C documentation and cookbook.)

In the code section, you're essentially just writing C code - but perl API functions can also be used.

Inline::C works by first creating an XS file, which you can find in the ./_Inline directory if you include CLEAN_AFTER_BUILD in the Config section of the script before building.

Cheers,
Rob

In reply to Re: help with XS pointers by syphilis
in thread help with XS pointers by Bpl

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