Hi,
your example makes it harder as necessary...
Besides, it does not actually do something. I'd assume it doesn't even compile properly.
Here's a working example (opening/closing the logfile is here replaced by reading from the DATA handle):

use strict;
use warnings;

my $infile = 'b2bclient-gateway-heartbeat.log';
my $outfile = 'results.txt';
my($fh_out, $fh);

open($fh_out, '>', $outfile) or die "Could not open outfile: $!";

# open($fh, '<', $infile) or die "Could not open logfile: $!";
# while (<$fh>) {
while (<DATA>) {
    /TWO/ && print $fh_out $_;
}

close $fh_out;
#close $fh;

__DATA__
2007-Nov-07 00:00:00 UTC (GMT +0000) - Poll: channel = ONE, ref =
2007-Nov-07 00:00:01 UTC (GMT +0000) - Poll: channel = TWO, ref =
2007-Nov-07 00:00:01 UTC (GMT +0000) - Poll: channel = TWO, ref =
2007-Nov-07 00:00:02 UTC (GMT +0000) - Poll: channel = THREE, ref =
2007-Nov-07 00:00:02 UTC (GMT +0000) - Poll: channel = TWO, ref =
2007-Nov-07 00:00:03 UTC (GMT +0000) - Poll: channel = TWO, ref =
2007-Nov-07 00:00:03 UTC (GMT +0000) - Poll: channel = TWO, ref =
2007-Nov-07 00:00:04 UTC (GMT +0000) - Poll: channel = TWO, ref =
[download]

Regards,
svenXY