use File::Tee;
my $logfile = "log.txt";
open(LOG, ">>$logfile");
flock(LOG, 2);
File::Tee::tee LOG, ">&STDOUT";

print LOG "some message\n";

&pager();

sub pager { 
        my $temp = "temp.txt";
        my $pager = "less"; 
        system("$pager $temp");
}