G'day davidinottawa,

I'd approach this in a number of different ways to what you've posted:

• Your input file appears to be pipe-separated CSV. Use Text::CSV: that's already done most of the work for you.
• Instead of attempting to hand-craft I/O error messages, use the autodie pragma. Hand-crafting messages is error-prone: your first only says why, not what; your second only says what, not why.
• Use the 3-argument form of open with lexical filehandles. You did this for your first open; however, the second uses a very generic package variable (i.e. INPUT) which could well be used elsewhere in your code (textually distant from the code you're looking at) and is therefore error-prone.
• I'd use a hash for storing your match patterns.

Putting all that together (pm_1153098_match_csv_lines.pl):

#!/usr/bin/env perl -l

use strict;
use warnings;
use autodie;

use Text::CSV;

my $input_file = 'pm_1153098_match_csv_lines_input.csv';
my $pattern_file = 'pm_1153098_match_csv_lines_pattern.txt';

my %match_pattern;
open my $pat_fh, '<', $pattern_file;
while (<$pat_fh>) {
    chomp;
    ++$match_pattern{$_};
} 
close $pat_fh;

my $csv = Text::CSV::->new({sep_char => '|'});
open my $in_fh, '<', $input_file;
while (my $row = $csv->getline($in_fh)) {
    print $row->[1] if $match_pattern{$row->[1]};
}
close $in_fh;
[download]

With these files:

$ cat pm_1153098_match_csv_lines_input.csv
David@domain.com|David@domain.com|J|ABBASS, DAVID JOHN|
Cory@domain.com|Cory@domain.com|E|ABBOTT, CORY J|
Tania@domain.com|Tania@domain.com|F|ABBOTT, TANIA LEE|
Geoffrey@domain.com|Geoffrey@domain.com|N|ABBOTT, GEOFFREY BRYAN|
[download]

$ cat pm_1153098_match_csv_lines_pattern.txt
Randall@domain.com
David@domain.com
Rob@domain.com
Tania@domain.com
[download]

I get this output:

$ pm_1153098_match_csv_lines.pl
David@domain.com
Tania@domain.com
[download]

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