my $LOG_FILE = "$HOME/log/test.txt";
open(LOG, "> $LOG_FILE") || die "Can't redirect stdout";
open (CMD, "ls |");
while (<CMD>)
{
      lprint ($_)
}
close(CMD);

sub lprint ()
{     
      my ($line) = @_;
      print LOG $line;  
      print $line;
}

##</code><code>##

From: open (CMD, "ls |");
To:   open (CMD, "ls_non_command |");