my $line;
while ($line = <>){
  print "$.\n" unless ($. % 10000);  # to keep track of the progress
}

##</code><code>##

my $in = FileHandle->new($ARGV[0]);
my $line;
while ($line = $in->getline){
	print "$.\n" unless ($. % 10000);
}

##</code><code>##

use IO::All;
my $in = io($ARGV[0]);
my $line;
while ($line = $in->getline){
	print "$.\n" unless ($. % 10000);
}