14.7 Screen Saver

To prevent monitor damage, an X server implements a screen saver function which blanks screens during periods of unuse. The screen saver can be in one of three states:

The following paragraphs describe the CLX functions used to:



activate-screen-saver display Function
        
display
A display.

Activates the screen saver for the display server.



reset-screen-saver display Function
        
display
A display.

Deactivates the screen saver for the display server (if necessary) and resets its timer, just as if a pointer or keyboard event had occurred.



screen-saver display Function
        
display
A display.

Returns the current control values for the display server screen saver. See set-screen-saver.

timeout, period
Type int16.
blanking, exposures
One of :yes or :no.


set-screen-saver display timeout period blanking exposures Function
        
display
A display.
timeout
Specifies the delay until timeout takes over.
period
Specifies the periodic change interval, if used.
blanking
Specifies whether the blanking option is available.
exposures
Specifies whether exposures are allowed during blanking.

Changes the current control values for the display server screen saver. The screen saver is reset. The screen saver is also disabled if:

  • timeout is zero, or
  • Both blanking and exposures are disabled and the server cannot regenerate the screen contents without sending :exposure events.

The timeout specifies the (non-negative) number of seconds of input device inactivity that must elapse before the screen saver is activated. The timeout can be set to :default to restore the server default timeout interval.

If blanking is :yes and the screen hardware supports blanking, blanking is enabled; that is, the screen saver will simply blank all screens when it is activated. blanking can be set to :default to restore the server default state for blanking.

If exposures is :yes, exposures are enabled. If exposures are enabled, or if the server is capable of regenerating screen contents without sending :exposure events, the screen saver will display some server-dependent image when activated. Frequently, this image will consist of a repeating animation sequence, in which case period specifies the ( non-negative) number of seconds for each repetition. A period of zero is a hint that no repetition should occur.