use Win32::Process::List;

my $P = Win32::Process::List->new();  #constructor
my @list = $P->GetProcesses();        #returns an array of hashes
my %h = %{ $list[0] };          #get the hash with processname and pid
foreach my $pr ( keys %h ) {
    print "Process $pr has PID " .  $h{$pr} . "\n";
}