Solved !

Ladies and Gentlemen, you REALLY made my day !
Thanks to all contributors !
Here is the working codesniplet:


sub download {


use CGI;

$html=new CGI;


#print $html->header(-type => 'application/octet-stream', -attachment 
+=> $_[1]);
print $html->header(-type => 'application/zip', -attachment => $_[1]);
+        
    open($peunter, "<", $_[0].$_[1]);
    binmode($peunter);
    binmode STDOUT;
    while (read($peunter,$bytes,1024)) {
            unless (eof()) {
            chomp($bytes);
            }
            print $bytes;
    }

    #@data = <$peunter>;
    
    close($peunter);
    
    #print "@data";


}

[download]
Sorting out the file structure exported in the zipfle downloaded, should be a matter of try and error...
Again: thanks a lot for all your hints !

Hello everybody ! First of all let me thank you for tons of hints and tips I have gathered from your forum already ! Yet today I am coming up with a question that I have been trying to look up for weeks, and in fact I did not even find my exact problem:

I am offering some files to download. In order to transport them all together in one leap my idea was to pack them in a zip-file, using archive::zip. Everything seems to be working just fine (no warnings, no errors, nothing) untill I try to open the zip file after the download. All programs on all platforms tested (Windows 7, 8, Mac OSX maverick) report a crc error, stating the files were corrupted. downloading the same files one by one, without zipping them works fine. I am posting my code cutting out those parts that deal with form data extraction and such stuff, assuming here can't be the reason. 

#!/usr/bin/perl
 

use warnings;
use Archive::Zip qw(:ERROR_CODES :CONSTANTS);


.
.
.

    
    use Archive::Zip qw( :ERROR_CODES :CONSTANTS );
    $zipName = "../downloads/".$verzeichnis."Download.zip";
    $zip = Archive::Zip->new();
    $index==0;
    foreach (@zumzippen) {
    ##use IO::Compress::Zip qw(:all);
    #use IO::Compress::Zip qw(:ZIP_CM_STORE);
    ##$status = zip [ @zumzippen ] => "../downloads/".$verzeichnis."Do
+wnload.zip"; # , Autoclose => 1; #Method => ZIP_CM_DEFLATE , Level =>
+ Z_NO_COMPRESSION;
    
    $member = $zip->addFile( $_ , @dateiliste[$index]);

    
    #$member->desiredCompressionMethod( COMPRESSION_STORED );
    
    #$crc = $zip->computeCRC32( $zipName  );  
    
  
    #$member->desiredCompressionLevel( 8 );
    $index++;
    }
    
#    $zip->addTree("../downloads/$verzeichnis", "$verzeichnis");
    
    
    #$status = $zip->writeToFileNamed("../downloads/".$verzeichnis.$zi
+pName);
    $status = $zip->writeToFileNamed($zipName);
}

[download]

As you can see, I also tried compress::zib with the same results. Any hints/help appreciated !

Thanks to Corion I can alter my question:
The zip file on disk is absolutely fine. Trouble starts when downloading it.
Sorry for confusing things and you guys !
Just in case you are not fed up with someone who doesn't even realise which script is causing the error,
Here comes the download script, again just the relevant part.:

#!/usr/bin/perl 
#use warnings;
.
.
.
sub download {


use CGI;

$html=new CGI;


print $html->header(-type => 'application/octet-stream', -attachment =
+> $_[1]);
        
    open($peunter, "<", $_[0].$_[1]);
    binmode($peunter);
    binmode STDOUT;
    while (read($pointer,$bytes,1024)) {
            print $bytes;
    }
    #@data = <$peunter>;
    
    close($peunter);
    
    #print "@data";


}

[download]

In reply to CRC Error on ZIP Files by SearchigPerl

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