#! perl slw
use strict;
use Win32::API::Prototype;

my $memoryStatus = AllocMemory( 32 );
ApiLink( 'Kernel32', 'GlobalMemoryStatus', 'P', 'V' );

GlobalMemoryStatus( $memoryStatus );
my @keys = qw[
    length PercentageLoad
    TotalPhysical AvailablePhysical
    TotalPaged AvailablePaged
    TotalVirtualMemory AvailableVirtualMemory
];

my %mStatus;
@mStatus{ @keys } = unpack 'V8', $memoryStatus;

printf '%30s : %.2f ', $/,
    $_, $mStatus{ $_ } / 2**20
    for @keys[ 1 .. $#keys ];

__END__
P:\test>gMem
                PercentageLoad : 0.00
                 TotalPhysical : 510.98
             AvailablePhysical : 360.27
                    TotalPaged : 1250.05
                AvailablePaged : 908.16
            TotalVirtualMemory : 2047.88
        AvailableVirtualMemory : 2018.61