XSGIvcSetOutputBlanking(3)XSGIvcSetOutputBlanking(3)
NAME
XSGIvcSetOutputBlanking, XSGIvcQueryOutputBlanking - Channel
Blanking Operations
SYNOPSIS
#include <X11/extensions/XSGIvc.h>
void XSGIvcSetOutputBlanking(Display *display,
int screen,
int channel,
Bool enable)
Status XSGIvcQueryOutputBlanking(Display *display,
int screen,
int channel,
Bool *enableReturn)
PARAMETERS
display Specifies the connection to the X server.
screen Specifies the screen of the X server.
channel Specifies the channel number.
enable Specifies whether blanking should be enabled.
enableReturn Returns whether blanking is enabled.
DESCRIPTION
Simple screen savers use this function to force the screen
to black.
When a channel is blanked, the active video portion of the
signal is disabled. The screen is drawn black; however,
normal video synchronization signals persist so the monitor
can remain locked. When blanking is disabled, the active
video is restored and the monitor once again displays
pictures.
XSGIvcSetOutputBlanking enables and disables blanking on a
channel. The value may be True or False.
XSGIvcQueryOutputBlanking returns the current settings for
blanking on a channel. The value may be True or False.
Interaction with Screen Saver
Some screen saver programs will simply blank the screen as
part or all of their function; the screen saver is
controlled by XSetScreenSaver, et al. The function of
OutputBlanking is independent of that supplied by that of
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XSGIvcSetOutputBlanking(3)XSGIvcSetOutputBlanking(3)
the screen saver, which uses a different mechanism to enable
and disable output. A channel will display only if the
screen saver is not active and blanking is not enabled; that
is, either one of the screen saver or blanking will disable
output to a channel.
EVENTS
When this control is altered, the server generates a
OutputBlankingNotify event.
RETURNED VALUE
XSGIvcQueryOutputBlanking returns TRUE if successful, FALSE
upon failure.
Parameter errors are reported via BadValue or BadMatch.
SEE ALSO
XSGIvc, XSetScreenSaver
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