In a script i'm working on, I create a ZIP archive and add a file to it. Or, if the zip file exists, just add the file to it. I have noticed a strange thing: I tell the script to add the same file to the ZIP archive many times, then open the archive with Winzip and what do I see? There are indeed many files inside - with the same filename! When I try to rename/delete those files, each of them is treated independently of others.

Even though this behaviour seems logical to me, I cannot reproduce the same functionality when I use PKZIP/Winzip/any other utility... Is that an 'undocumented feature' of Perl or what?

The code used is here:

use Archive::Zip qw(:CONSTANTS :ERROR_CODES);
use IO::Scalar;

my $fname = 'file1.txt';
my $zipfile = 'filename.zip';
my $zip = Archive::Zip -> new();
if (-e $zipfile)
{
   $zip ->read($zipfile);
} 

my $member = $zip->memberNamed( $fname );
if ($member eq undef)
{
   $member = $zip->addFile( $fname );
}

$member -> desiredCompressionLevel( 9 );

$fname = 'autotransParams.txt';
$member = $zip->memberNamed( $fname );
if ($member eq undef)
{
   $member = $zip->addFile( $fname );
}

$member -> desiredCompressionLevel( 9 );
my $status = $zip -> overwriteAs($zipfile);
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