I need to zip a bunch of files, and due to the fact that I have a few extra CPU cycles to spare, I want to use maximum compression. The issue I am running into is that when I specify the maximum compression within the script, it does not seem to be honored. Regardless of what I try, the default desiredCompressionLevel is always used.

According to Archive/Zip.pm:

use constant COMPRESSION_DEFLATED               => 8; # file is Deflat
+ed
use constant COMPRESSION_LEVEL_DEFAULT          => -1;
use constant COMPRESSION_LEVEL_FASTEST          => 1;
use constant COMPRESSION_LEVEL_BEST_COMPRESSION => 9;

[download]
Here's an example script: 
#!/bin/perl -w
use strict;
use Archive::Zip qw(:ERROR_CODES :CONSTANTS); #$VERSION = '1.30';

die "usage: $0 zipfile.zip file [...]\n"
    if (scalar(@ARGV) < 2);

my $zipName = shift(@ARGV);
my $zip = Archive::Zip->new();

foreach my $memberName (map { glob } @ARGV){
    my $member = $zip->addFile( $memberName )
        or warn "Can't add file $memberName\n";
    #$member->desiredCompressionMethod( COMPRESSION_DEFLATED );
    $member->desiredCompressionLevel( 9 );
}

my $status = $zip->writeToFileNamed($zipName);

my $zipread = Archive::Zip->new();
$zipread->read( $zipName );

foreach my $member ($zipread->members()){
    print $member->fileName()."\t",
        $member->compressionMethod()."\t",
        $member->desiredCompressionMethod()."\n";
}

exit $status;

[download]
Expected output:
filename.log 8 9

Actual output:
filename.log 8 8

Thanks for the help

In reply to Archive::Zip not honoring desiredCompressionMethod by msalerno

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