How to determine that a screensaver is running?

Question

One solution that one could suggest is to periodically look for a special \'Screen-saver\' desktop, and if it\'s present then count it as a running screensaver.

But

Answer 1

See the WINAPI function SystemParametersInfo() with the SPI_GETSCREENSAVERRUNNING parameter. It's the only documented way to detect whether the screen saver is currently running. (You can also find out if a screen saver is even enabled, get and set the timeout value, and start the screen saver using this function.)