my $report_files_dir = "../Working/New_data";

my $filename_pattern = "Remedy.csv";

$interface_file = "nodes.csv";

open ( my $interface_data, "<", "$report_files_dir/$interface_file" ) or die $!;

opendir ( my $report_files, $report_files_dir) || die "can't opendir $report_files_dir: $!";

for ( sort readdir $report_files ) {
	next unless $_ =~ /$filename_pattern/;
	
	open ( my $remedy_file, "<", "$report_files_dir/$_" ) or die $!;

	while (<$remedy_file>) {
		chomp;
		next if ($. == 1);

		# Parse info from the current line
		# Use a returned value ($first_node) to look up data in another file:
		
		LOOKUP: while (<$interface_data>) {
			chomp;
			my @list = split/\|/;
			my $ref_id = &clean( $list[2] );
						
			if ( $ref_id =~ /$first_node/ ) {
			
				# The CMTS name is in Column 0
				$cmts_name = $list[0];
				
				# The CMTS Interface is in Column 1
				$cmts_interface = $list[1];
				
				last LOOKUP;
			}
		}
		seek ( $interface_data, 0, 0 );

		# Finish doing the report generation...

	}
	close ( $remedy_file );
}

closedir ( $report_files );
close ( $benchmark_data );
close ( $interface_data );
close ( $progress_file );

##</code><code>##

Use of uninitialized value in subtraction (-) at ./load_Remedy.pl line 503, <$interface_data> line 1894801.
Use of uninitialized value in subtraction (-) at ./load_Remedy.pl line 503, <$interface_data> line 5825736.
Use of uninitialized value in subtraction (-) at ./load_Remedy.pl line 503, <$interface_data> line 6546698.