NAME

       XSetScreenSaver, XForceScreenSaver, XActivateScreenSaver, XResetScreenSaver,
       XGetScreenSaver - manipulate the screen saver

SYNTAX

       int XSetScreenSaver(Display *display, int timeout, int interval, int prefer_blanking, int
              allow_exposures);

       int XForceScreenSaver(Display *display, int mode);

       int XActivateScreenSaver(Display *display);

       int XResetScreenSaver(Display *display);

       int XGetScreenSaver(Display *display, int *timeout_return, int *interval_return, int
              *prefer_blanking_return, int *allow_exposures_return);

ARGUMENTS

       allow_exposures
                 Specifies the screen save control values.  You can pass DontAllowExposures,
                 AllowExposures, or DefaultExposures.

       allow_exposures_return
                 Returns the current screen save control value (DontAllowExposures,
                 AllowExposures, or DefaultExposures).

       display   Specifies the connection to the X server.

       interval  Specifies the interval, in seconds, between screen saver alterations.

       interval_return
                 Returns the interval between screen saver invocations.

       mode      Specifies the mode that is to be applied.  You can pass ScreenSaverActive or
                 ScreenSaverReset.

       prefer_blanking
                 Specifies how to enable screen blanking.  You can pass DontPreferBlanking,
                 PreferBlanking, or DefaultBlanking.

       prefer_blanking_return
                 Returns the current screen blanking preference (DontPreferBlanking,
                 PreferBlanking, or DefaultBlanking).

       timeout   Specifies the timeout, in seconds, until the screen saver turns on.

       timeout_return
                 Returns the timeout, in seconds, until the screen saver turns on.

DESCRIPTION

       Timeout and interval are specified in seconds.  A timeout of 0 disables the screen saver
       (but an activated screen saver is not deactivated), and a timeout of -1 restores the
       default.  Other negative values generate a BadValue error.  If the timeout value is
       nonzero, XSetScreenSaver enables the screen saver.  An interval of 0 disables the random-
       pattern motion.  Both values are limited to a 16-bit signed integer range by the wire
       protocol, despite the C prototype.  If no input from devices (keyboard, mouse, and so on)
       is generated for the specified number of timeout seconds once the screen saver is enabled,
       the screen saver is activated.

       For each screen, if blanking is preferred and the hardware supports video blanking, the
       screen simply goes blank.  Otherwise, if either exposures are allowed or the screen can be
       regenerated without sending Expose events to clients, the screen is tiled with the root
       window background tile randomly re-origined each interval seconds.  Otherwise, the
       screens' state do not change, and the screen saver is not activated.  The screen saver is
       deactivated, and all screen states are restored at the next keyboard or pointer input or
       at the next call to XForceScreenSaver with mode ScreenSaverReset.

       If the server-dependent screen saver method supports periodic change, the interval
       argument serves as a hint about how long the change period should be, and zero hints that
       no periodic change should be made.  Examples of ways to change the screen include
       scrambling the colormap periodically, moving an icon image around the screen periodically,
       or tiling the screen with the root window background tile, randomly re-origined
       periodically.

       XSetScreenSaver can generate a BadValue error.

       If the specified mode is ScreenSaverActive and the screen saver currently is deactivated,
       XForceScreenSaver activates the screen saver even if the screen saver had been disabled
       with a timeout of zero.  If the specified mode is ScreenSaverReset and the screen saver
       currently is enabled, XForceScreenSaver deactivates the screen saver if it was activated,
       and the activation timer is reset to its initial state (as if device input had been
       received).

       XForceScreenSaver can generate a BadValue error.

       The XActivateScreenSaver function activates the screen saver.

       The XResetScreenSaver function resets the screen saver.

       The XGetScreenSaver function gets the current screen saver values.

DIAGNOSTICS

       BadValue  Some numeric value falls outside the range of values accepted by the request.
                 Unless a specific range is specified for an argument, the full range defined by
                 the argument's type is accepted.  Any argument defined as a set of alternatives
                 can generate this error.

SEE ALSO

       Xlib - C Language X Interface