After some quick digging in the MSDN, there is no WMI query but you have to use the raw Win32 API to access the tick count of the computer and the timestamp (in ticks) since the last user input. From the difference between the two you can determine the time the user has been idle (or rather, has been making no input, maybe because he's discussing some issue on the screen):

#!/usr/bin/perl -w
use strict;
use Win32::API;
use POSIX qw(strftime);
use Data::Dumper;

my $GetLastInputInfo = Win32::API->new("user32.dll",'GetLastInputInfo'
+,'P','I');
my $GetTickCount = Win32::API->new("kernel32.dll",'GetTickCount','','I
+');

sub get_user_idle_time {
    my $buffer = pack "VV", 8,0;
    $GetLastInputInfo->Call($buffer)
        or die "Couldn't call GetLastInputInfo: $^E";
    my ($size,$time) = unpack "VV", $buffer;
    my $now = $GetTickCount->Call;

    # Adjust time to return a reference in seconds
    return int (($now-$time) / 1000);
};


while (1) {
    print strftime( "Idle since %M:%S\n", localtime(get_user_idle_time
+));
    sleep(2);
};

[download]

In reply to Re: Detect if Windows screensaver is running or screen is locked (Lock Computer) by Corion
in thread Detect if Windows screensaver is running or screen is locked (Lock Computer) by nicc777

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