Well, I have two things to say to that. First, you get what you ask for if you make assumptions about the knowledge of the people helping you. Second, the first time I mentioned $ not really being there should have been an indication to you that I didn't know what I was talking about. In any event, here is a working proof of concept since you have had to suffer through my ignorance.

#!/usr/bin/perl
use strict;
use warnings;

my $file = $ARGV[0] || 'foo.txt';

open(my $fh, '<', $file) or die "Unable to open '$file' for reading: $
+!";

my $buffer = '';
while (<$fh>) {
    if (/^\S+domain\.com$/) {
        process_buffer($buffer);
        $buffer = $_;
        next;
    }
    $buffer .= $_;
}

sub process_buffer {
    my ($section) = @_;
    print "================BLAH================\n$section\n";
}
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