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