my $blank_lines = 0;
while (<>) {
    if ($_ eq "\n") { ++$blank_lines }
    else {
        print "\n" x $blank_lines if $blank_lines != 1;
        print;
        $blank_lines = 0;
    }
}

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In reply to Re: remove single blank lines? by Roy Johnson
in thread remove single blank lines? by aloomens

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