Hello natol44,

Have you looked at the 3rd optional parameter of 'index'. 'index' is very fast and since you have a large string, you can loop until the end by starting the next search('index') with the end of the most recent end of your search. (untested code):

   my $pos = 0;
   while ( $pos < length( $all ) )
   {    my $si = index ( $all, "<START>", $pos );
        if ( $si < 0 ) { last; }
        my $sj = index ( $all, "<END>", $si+1 );
        if ( $sj > $si+1 )
        {    ... Collect you string with 'substr' etc.
        }
        $pos = $sj + 4;     # set search for finding next text.
   }
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Note: There are working examples in the Perl Cookbook and also using Super Search.

Regards...Ed