#!/usr/bin/perl

 use strict;
 use warnings;

 while(<DATA>) {
     print if range_op( scalar(/start/), scalar(/end/) );
 }

BEGIN {
 my( $true, $false ) = ( 1, 0 );

 my $state = $false;

 sub range_op {
     my( $term_l, $term_r ) = @_;

     if( $state == $true ) {
         $state = $false if $term_r == $true;

         return $state;
     }
     
     $state = $true if $term_l == $true;
     return 0;
 }

}
_ _DATA_ _
 nichts
 nichts
start
 eins
 zwei
 drei
end
 nichts
 nichts
start
 vier
 fuenf
 sechs
end