The following produces the output you describe, except for the bolding. For hilighting you might have a look at Term::ANSIColor.

#!/usr/bin/perl

use strict;
use warnings;

my $qfn1 = "File1.txt";
my $qfn2 = "File2.txt";

my %positions;
{
   open(my $fh, '<', $qfn1)
      or die("Cannot open file \"$qfn1\": $!\n");

   while (<$fh>) {
      my ($key, $pos) = split /\s+/;
      $positions{$key} = $pos;
   }
}

{
   open(my $fh, '<', $qfn2)
      or die("Cannot open file \"$qfn2\": $!\n");

   for (;;) {
      defined( my $key = <$fh> )
         or last;
      defined( my $text = <$fh> )
         or last;
      chomp($key);
      chomp($text);

      $key = (split(/\|/,$key,3))[1];

      defined( my $pos = $positions{$key} )
         or next;
      
      my $index = rindex($text, "FAN", $pos);
      next if ( $index < 0 );

      $index += 3 while ( ($index + 3) < $pos);

      print "$key $pos " . substr($text, $index, 3) . "\n";

   }
}

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In reply to Re: Extracting Locations in 3 window size by ig
in thread Regex problem by ashnator

Title:
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