Since s/he is planning to output this to the browser, you'd think the writeToFileHandle() method will suffice (to STDOUT). If s/he does wind up needing it in a scalar (for some perverse reason, I can think of no good reason for needing this), s/he could use something like this to get the contents of $zip into $scalar:

# recent perl's:
open( my $fh, '>', \my $scalar ) or die "open failed: $!";
$zip->writeToFileHandle($fh);

# recent & odler perl's:
use IO::Scalar;
# or:
# use IO::String (apparently more recent than IO::Scalar)

my $fh = IO::Scalar->new(\my $scalar);
$zip->writeToFileHandle($fh);
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