All I have to say is eew, you made me look inside Audio::Wav :) all that Inline::C noise is ridiculous

I can confirm this is a bug in Audio::Wav, its not closing the filehandles, in both the ridiculous Inline::C version and the pure-perl version, because of circular references (a closure, mentioned in Changes file)

If you add

use DDS; exit print "\n\n", Dump( { readwav => $readwav, read => $read
+, src_details => $src_details } );
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You can see the "closure"

my ($block,$channels,$handle,$self);
$block = 1;
$channels = 1;
$handle = bless( do{ require Symbol; Symbol::gensym }, 'FileHandle' );
$self = bless( {
          data    => {
                       bits_sample  => 8,
                       block_align  => 1,
                       bytes_sec    => 8000,
                       channels     => 1,
                       cue          => { 1 => {
                                         bstart   => 0,
                                         chunk    => 'data',
                                         cstart   => 0,
                                         offset   => 2179,
                                         position => 2179
                                       } },
                       data_finish  => 4044,
                       data_length  => 4000,
                       data_start   => 44,
                       labl         => { 1 => 'Cue 1' },
                       length       => 0.5,
                       note         => { 1 => 'cue point' },
                       sample_rate  => 8000,
                       total_length => 4152,
                       "wave-ex"    => 0
                     },
          file    => '...Audio-Wav-0.12\\xt/../test_tone.wav',
          handle  => $handle,
          pos     => 44,
          read_sub
                  => sub {
                       package Audio::Wav::Read;
                       use strict 'refs';
                       my $val;
## THIS IS THE CLOSURE, the reference to $handle lives forever
                       $$self{'pos'} += read($handle, $val, $block);
                       return unless defined $val;
                       return map(($_ - 128), unpack('C' . $channels, 
+$val));
                     },
          read_sub_string
                  => "\n        sub {\n            my \$val;\n        
+    \$self -> {'pos'} += read".
    "( \$handle, \$val, \$block );\n            return unless defined 
+\$val;\n     ".
    "        return map \$_ - 128, unpack( 'C'.\$channels, \$val ); \n
+        };\n".
    "    ",
          real_size
                  => 4160,
          tools   => bless( {
                       ".01compatible" => 0,
                       debug           => 0,
                       errorHandler    => undef,
                       oldcooledithack => 0
                     }, 'Audio::Wav::Tools' )
        }, 'Audio::Wav::Read' );
$HASH1 = {
           read        => $self,
           readwav     => bless( { tools => $self->{tools} }, 'Audio::
+Wav' ),
           src_details => $self->{data}
         };
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#!/usr/bin/perl --
BEGIN { 
    use File::Spec;
    use File::Basename qw' dirname ';
    our $thisf = File::Spec->rel2abs(__FILE__);
    our $thisd = dirname($thisf);
}

use Audio::Wav;

my $wav = "$thisd/../test_tone.wav";

$Audio::Wav::_has_inline ||= $ENV{'--useInlineCanyway'};
$Audio::Wav::_has_inline ||= grep /--useInlineCanyway/ , @ARGV;
warn "Audio::Wav::_has_inline => $Audio::Wav::_has_inline \n";

$|=1;
eval {
    for my $ix ( 1 .. ( 2045 + 10 ) ){
        print "\r$ix ";
        print "\n" if $ix > 2044;
        my $readwav = new Audio::Wav;
        my $read = $readwav -> read( $wav );
        my $src_details = $read -> details();
##        $read->{handle}->close; ## workaround
        $readwav = undef;
        $read = undef;
    }
} or warn $@;

system qw[ D:/sysinternals/SysinternalsSuite/handle.exe -p ], $$;
__END__
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