I modified my code as such:

my @lines;
my $command;
$command = "tail -$num $logfile";
@lines = ($t1->cmd('$command'));
print "@lines";

The tail command does not seem to be executed. Nothing is printed to the screen. Any advice?

Remember that single quotes supress variable interpolation...so '$command' will not be interpreted as it's contents...try

$t1->cmd($command);
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