Re: question on implementing C function with binary string as input and output

From: Perf Tech

> In another word, the C function should have the similar syntax as the 
> following perl function.
>
> sub myRepeat {
> my $str = shift;
> return $str . $str;
> }

I don't know (off the top of my head) how to concatenate binary strings in 
C, but the following demonstrates one way of successfully passing binary 
strings between perl and C:

##############################
use warnings;
use strict;
use Devel::Peek;

use Inline C => Config =>
BUILD_NOISY => 1,
;

use Inline C => <<'EOC';

SV * foo(SV * in) {
  STRLEN len;
  char *tmp = SvPV(in, len);
  return newSVpv(tmp, len);
}

EOC

my $in = 'hello' . "\x00" . 'world';
my $ret = foo($in);

$ret eq $in ? print "\nok 1\n\n"
            : print "\nnot ok 1\n\n";

Dump($in);
print "\n";
Dump ($ret);
##############################

Let us know if you need additional help with the concatenation aspect (or 
anything else, for that matter ;-)

Cheers,
Rob