Use the built-in Perl feature for input record separator splitting, perhaps?

use warnings;
use strict;
use Data::Dumper;
{
        local $/ = "\nXXX\n";
        while (my $record = <DATA>) {
                # remove the separator from the record
                $record =~ s{\Q$/\E$}{};
                print Dumper $record;
                # process the record here
        }
};
__DATA__
This is a test.
XXX
This is a multiline
test.
XXX
[download]

$VAR1 = 'This is a test.';
$VAR1 = 'This is a multiline
test.';
[download]

This may be useful if your file becomes impractical to fit in the RAM and you only need to process it record-by-record.