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

use Inline C;
      
    $arref = get_data();
    
    print $arref, "\n";

    print $arref->[0]->{mickey}, "\n";
    print $arref->[0]->{donkey}, "\n";


__END__
__C__

 SV* get_data() {
    AV * results;
    HV * rh = newHV();

    results = newAV();

    hv_store(rh, "mickey", 6, newSVpv("mouse", 0), 0);
    hv_store(rh, "donkey", 6, newSVpv("kong", 0), 0);
 
    av_push(results,newRV_noinc((SV*)rh));

    return newRV_noinc((SV*)results);

}
[download]

Changed a little your code to print out the keys as well as the values. De-referencing the hash is now ok, see code below. Thanks to you and ikegami for being so responsive, it helped me on my way. PS: indeed BUILD NOISY option is very informative.

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

use Inline C;
      
    $arref = get_data();
    
    print $arref, "\n";

    $href = $arref->[0];

    foreach my $key (sort keys %$href) {
    
       # print "v1 Key: ", $key, " => Value: ", $arref->[0]->{$key}, "
+\n";
       print "v2 Key: ", $key, " => Value: ", $href->{$key}, "\n";

    }


__END__
__C__

 SV* get_data() {
    AV * results;
    HV * rh = newHV();

    results = newAV();

    hv_store(rh, "mickey", 6, newSVpv("mouse", 0), 0);
    hv_store(rh, "donkey", 6, newSVpv("kong", 0), 0);
 
    av_push(results,newRV_noinc((SV*)rh));

    return newRV_noinc((SV*)results);

}
[download]

Hi Rob, "Couldn't get your code", well here's the recipe, get a windows box (heheheh ;-)), with active state perl installed (mine is currently 5.10.0), ppm install mingw. At least this works for me. It also works for me with visual studio 2005. Made a copy of the vsvars32.bat file and added "perl.exe %1" as the last line in this file. Invoking perl scripts with this bat file works also fine, and uses MS's nmake instead of MinGW's dmake. Anyway, you can be sure I'll test out your code asap and come back to comment. Thank you very much for your reply ! Really appreciate, Bruno

"Couldn't get your code to work", not "Couldn't get your code"

I don't know if it addresses your question at all, but I see major errors.

The only thing that should be mortal is the RV you return. Everything else is being referenced.

The fourth argument of hv_store is documented to be an SV*. I don't see how what you have could even compile.

SV* get_data() {
  AV * results;
  I32 nr = 0;
  int n;
 
  results = newAV();
 
  for (n = 0; n <= nr; n++) {
    HV * rh = newHV();

    {
       SV * val = newSVpv("mouse", 0);
       hv_store(rh, "mickey", 6, val, 0);
    }

    {
       SV * val = newSVpv("kong", 0);
       hv_store(rh, "donkey", 6, val, 0);
    }
 
    av_push(results, newRV_noinc((SV*)rh));
  }
 
  return newRV_noinc((SV*)results);
}
[download]

Untested.

The usage of newRV is not documented, so I used newRV_noinc.

Your loop is completely useless, but I left it in since I figure you would eventually use it.

First of all, thank you very much having a look at it. I am quite new to inline c, xs, I am still on the steep curve leraning the perl c api. As you mention the loop is completely useless, but this is on purpose. I want to return more hashes later, just 1 suffices for now. For the compilateion, it compiles fine with active state perl 5.10 with dmake (after installing minwg ppm module) as wel as with nmake (with visual studio environment). I will test out your suggestions above. Many Thanks,

Hello Ikegami, Indeed, the 4th argument should be a SV*, naïve try from me, but yep I'm an inline - xs beginner. The code works just by changing :

.....
hv_store(rh, "donkey", 6, "kong", 0);
.....
[download]

to :

.....
hv_store(rh, "donkey", 6, newSVpv("kong", 0), 0);
.....
[download]

The key-value pairs are now printed out as one expects. As pointed out by you it's maybe better indeed to use the documented newRV_noinc function. Curious to sort out the differences between the two. Many thanks for your time, Cheers, Bruno

Curious to sort out the differences between the two.

Not much...

#define newRV_inc(sv)   newRV(sv)
[download]

"newRV_inc is the official function name to use now." according to a comment.