Win32: Detecting when system is locked or sleeping

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    rod> I have written an application which works perfectly when the
    rod> machine is operating under normal conditions, however when the
    rod> screen becomes locked it imediately starts to fill up several
    rod> hundred MB's of memory.

What do you mean by "locked"?  Unresponsive to mouse or keyboard activity?
Blue screen?  What is your application doing while it's filling up memory?
Which memory, disk or RAM?

    rod> Is there a way to detect when the system is locked? 

Perhaps Nagios can help: <http://www.nagios.org/>.  In general, I don't
think a system can be relied upon to detect its own demise, as the recent
PC/Mac commercial about restarting illustrates:
<http://www.apple.com/getamac/ads/>.

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