There are quite a few issues with your script, if you put these two lines at the top you will get an idea: 
use strict;
use warnings;

[download]
See The strictures, according to Seuss for why.

To fix the most obvious try this (untested): 

my %map = ();

while (<IN>) {
    chomp $_;
    my @items = split(/\,/, $_);
    $map{$items[0]} = $items[1]; # [1] not [2]
}
close IN;

my ($cur_awb,$cur_val);

while (<BASE>) {
    chomp $_;

    if ($_ =~ m/\<KEY_BOL_REF\>(\d*)\<\/KEY_BOL_REF\>/) {
        $cur_awb = $1;
        $cur_val = $map{$cur_awb}; # should do some error check here
        print OUT $_ . "\n";
    }
    # ... etc.
}

[download]

In reply to Re: find text in xml tag and replace another tag from data in same txt file by tangent
in thread find text in xml tag and replace another tag from data in same txt file by alexlabelle

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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