Okaay... that will do: 

#!/usr/bin/perl
use Getopt::Std;
my %o;
getopt 'b:a:',\%o;
my $pat = shift;
my @last; 
OUTER: while(<>) {
    if (/$pat/) {
        @last = ();
        for my $i(1..$o{a}) {
            $_ = <>;
            redo OUTER if /$pat/;
        }
        next;
    }   
    push @last, $_;
    print shift @last if $o{b} < @last;
}
print @last;

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In reply to Re^3: Regex question by shmem
in thread Regex question by jamsda

Title:
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