#!/usr/bin/perl -w
use strict;
use Data::Dumper;

use Win32::SerialPort;
use Win32::OLE('in');
use constant wbemFlagReturnImmediately => 0x10;
use constant wbemFlagForwardOnly => 0x20;

my $computer = ".";

my $objWMIService = Win32::OLE->GetObject
    ("winmgmts:\\\\$computer\\root\\CIMV2") 
    or die "WMI connection failed.\n";
    
my $colItems = $objWMIService->ExecQuery
    ("SELECT * FROM Win32_SerialPortConfiguration",
     "WQL",wbemFlagReturnImmediately | wbemFlagForwardOnly);

foreach my $objItem (in $colItems)
{
    print "Caption: $objItem->{Caption}\n";
    print "Name: $objItem->{Name}\n";
}
__END__
prints:
Caption: COM1
Name: COM1