PV checks whether the scalar is a string. Use PVX to get the string buffer regardless of whether the scalar is a string. Since PV and PVX can only be called on subclasses of B::PV, you might want to check if you have the right class first. 
my $x = $sv->can('PVX') ? $sv->PVX : undef;

[download]

But why are you checking that?! It's equally correct for it to be present and absent. 

use strict;
use warnings;

use Test::More tests => 3;

use Devel::Peek;
use B qw( svref_2object SVf_IOK SVf_NOK SVf_POK );

sub is_iv {
   my $sv = svref_2object(my $ref = \$_[0]);
   my $flags = $sv->FLAGS;

   my $pv = $sv->can('PVX') ? $sv->PVX : undef;
  
   if (wantarray) {
       return ($flags & SVf_IOK, $pv);
   } else {
       return $flags & SVf_IOK;
   }
}

my $r = "100";
$r = 100;
Dump($r);

my ($iv, $pv) = is_iv($r);

is($r, 100, "correct value returned SQL_INTEGER");
ok($iv, "ivok bind integer");
ok($pv, "pv not null bind integer");

[download]

In reply to Re: Confusion over B::PV by ikegami
in thread Confusion over B::PV by mje

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