I was attempting to use the following code from Archive:Zip examples on Windows: 
# Example of how to compute compressed sizes
# $Revision: 1.2 $
use strict;
use Archive::Zip qw(:ERROR_CODES);
require File::Spec::Win32;
my $zip = Archive::Zip->new();
my $blackHoleDevice = File::Spec::Win32->devnull();

$zip->addFile($_) foreach (<*.pl>);

# Write and throw the data away.
# after members are written, the writeOffset will be set
# to the compressed size.
$zip->writeToFileNamed($blackHoleDevice);

my $totalSize = 0;
my $totalCompressedSize = 0;
foreach my $member ($zip->members())
{
    $totalSize += $member->uncompressedSize;
    $totalCompressedSize += $member->_writeOffset;
    print "Member ", $member->externalFileName,
    " size=", $member->uncompressedSize,
    ", writeOffset=", $member->_writeOffset,
    ", compressed=", $member->compressedSize,
    "\n";
}

print "Total Size=", $totalSize, ", total compressed=", $totalCompress
+edSize, "\n";

$zip->writeToFileNamed('test.zip');

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However, while it worked on Linux, OSX, it was a failure on Windows. BTW: while stepping through the debugger i saw that the scalar $blackHoleDevice was set to 'nul' not the usual Windows /dev/null device 'NUL'. However even it it was then set to 'NUL' it still did not work. When $blackHoleDevice was replaced by an actual file name it worked fine, but one assumes that the use of /dev/null was used to avoid the actual creation of a file. Question: is this just windows or me?

In reply to Usage of File::Spec->devnull() on Windows by chazubell

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