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'  states  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

X Version 11                                      libX11 1.8.7                                XSetScreenSaver(3)