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XkbDeviceBellEvent(3)		 XKB FUNCTIONS		 XkbDeviceBellEvent(3)

       XkbDeviceBellEvent  - Creates a bell event for an X input extension de-
       vice or for the keyboard, without ringing the corresponding bell

       Bool XkbDeviceBellEvent (Display	*display, Window window, unsigned  int
	      device_spec,  unsigned int bell_class, unsigned int bell_id, int
	      percent, Atom name);

       - display
	      connection to the	X server

       - window
	      event window, or None

       - device_spec
	      device ID, or XkbUseCoreKbd

       - bell_class
	      input extension bell class for the event

       - bell_id
	      input extension bell ID for the event

       - percent
	      volume for the bell, which can range from	-100 to	100 inclusive

       - name a	bell name, or NULL

       The core	X protocol allows only applications to	explicitly  sound  the
       system  bell with a given duration, pitch, and volume. Xkb extends this
       capability by allowing clients to attach	symbolic names to bells,  dis-
       able  audible bells, and	receive	an event whenever the keyboard bell is
       rung. For the purposes of this document,	the audible bell is defined to
       be  the	system	bell,  or the default keyboard bell, as	opposed	to any
       other audible sound generated elsewhere in the system.  You can ask  to
       receive	XkbBellNotify events when any client rings any one of the fol-

       o    The	default	bell

       o    Any	bell on	an input device	that can be specified by a  bell_class
	    and	bell_id	pair

       o    Any	 bell  specified only by an arbitrary name. (This is, from the
	    server's point of view, merely a name, and not connected with  any
	    physical  sound-generating	device.	 Some  client application must
	    generate the sound,	or visual feedback, if any, that is associated
	    with the name.)

	    You	 can  also ask to receive XkbBellNotify	events when the	server
	    rings the default bell or if any client has	requested events  only
	    (without  the  bell	sounding) for any of the bell types previously

	    You	can disable audible bells on a global basis.  For  example,  a
	    client that	replaces the keyboard bell with	some other audible cue
	    might want to turn off the	AudibleBell  control  to  prevent  the
	    server  from  also	generating a sound and avoid cacophony.	If you
	    disable audible bells and request to receive XkbBellNotify events,
	    you	can generate feedback different	from the default bell.

	    You	 can, however, override	the AudibleBell	control	by calling one
	    of the functions that force	the ringing of a bell in spite of  the
	    setting  of	 the  AudibleBell control - XkbForceDeviceBell or Xkb-
	    ForceBell.	In this	case the  server  does	not  generate  a  bell

	    Just  as  some  keyboards can produce keyclicks to indicate	when a
	    key	is pressed or repeating, Xkb can provide feedback for the con-
	    trols  by using special beep codes.	The AccessXFeedback control is
	    used to configure the specific types of operations	that  generate

	    Bell Names

	    You	can associate a	name to	an act of ringing a bell by converting
	    the	name to	an Atom	and then using this name  when	you  call  the
	    functions  listed  in  this	chapter. If an event is	generated as a
	    result, the	name is	then passed to all other clients interested in
	    receiving  XkbBellNotify  events.  Note  that  these are arbitrary
	    names and that there is no binding to any sounds.  Any  sounds  or
	    other  effects (such as visual bells on the	screen)	must be	gener-
	    ated by a client application upon receipt of the bell  event  con-
	    taining  the  name.	 There is no default name for the default key-
	    board bell.	The server does	generate some predefined bells for the
	    AccessX  controls.	These named bells are shown in the Table 1 be-
	    low; the name is included in any bell event	sent to	 clients  that
	    have requested to receive XkbBellNotify events.

			      Table 1 Predefined Bells
	    Action				       Named Bell
	    Indicator turned on			       AX_IndicatorOn
	    Indicator turned off		       AX_IndicatorOff
	    More than one indicator changed state      AX_IndicatorChange
	    Control turned on			       AX_FeatureOn
	    Control turned off			       AX_FeatureOff
	    More than one control changed state	       AX_FeatureChange
	    SlowKeys  and  BounceKeys  about  to  be   AX_SlowKeysWarning
	    turned on or off
	    SlowKeys key pressed		       AX_SlowKeyPress
	    SlowKeys key accepted		       AX_SlowKeyAccept
	    SlowKeys key rejected		       AX_SlowKeyReject
	    Accepted SlowKeys key released	       AX_SlowKeyRelease
	    BounceKeys key rejected		       AX_BounceKeyReject
	    StickyKeys key latched		       AX_StickyLatch
	    StickyKeys key locked		       AX_StickyLock
	    StickyKeys key unlocked		       AX_StickyUnlock

	    Audible Bells

	    Using Xkb you can generate bell events  that  do  not  necessarily
	    ring  the system bell.  This is useful if you need to use an audio
	    server instead of the system beep.	For  example,  when  an	 audio
	    client starts, it could disable the	audible	bell (the system bell)
	    and	then listen for	 XkbBellNotify	events.	 When  it  receives  a
	    XkbBellNotify event, the audio client could	then send a request to
	    an audio server to play a sound.

	    You	can control the	audible	bells feature by passing the  XkbAudi-
	    bleBellMask	 to  XkbChangeEnabledControls.	If you set XkbAudible-
	    BellMask on, the server rings the system bell when	a  bell	 event
	    occurs. This is the	default. If you	set XkbAudibleBellMask off and
	    a bell event occurs, the server does not ring the system bell  un-
	    less you call XkbForceDeviceBell or	XkbForceBell.

	    Audible bells are also part	of the per-client auto-reset controls.

	    Bell Functions

	    Use	 the  functions	described in this section to ring bells	and to
	    generate bell events.

	    The	input extension	has two	types of feedbacks that	 can  generate
	    bells - bell feedback and keyboard feedback. Some of the functions
	    in this section have bell_class and	bell_id	parameters;  set  them
	    as	follows:  Set  bell_class to BellFeedbackClass or KbdFeedback-
	    Class. A device can	have more than one feedback of each type;  set
	    bell_id to the particular bell feedback of bell_class type.

	    Table  2  shows  the  conditions  that cause a bell	to sound or an
	    XkbBellNotifyEvent to be generated when a bell function is called.

			 Table 2 Bell Sounding and Bell	Event Generating
	    Function called	 AudibleBell   Server sounds a bell   Server sends an
	    XkbDeviceBell	 On	       Yes		      Yes
	    XkbDeviceBell	 Off	       No		      Yes
	    XkbBell		 On	       Yes		      Yes
	    XkbBell		 Off	       No		      Yes
	    XkbDeviceBellEvent	 On or Off     No		      Yes
	    XkbBellEvent	 On or Off     No		      Yes
	    XkbDeviceForceBell	 On or Off     Yes		      No
	    XkbForceBell	 On or Off     Yes		      No

	    If a compatible keyboard extension isn't present in	the X  server,
	    XkbDeviceBellEvent	immediately  returns  False. Otherwise,	XkbDe-
	    viceBellEvent causes an XkbBellNotify event	to be sent to all  in-
	    terested  clients  and  returns True. Set percent to be the	volume
	    relative to	the base volume	for  the  keyboard  as	described  for

	    In	addition, XkbDeviceBellEvent may generate Atom protocol	errors
	    as well as XkbBellNotify events.  You  can	call  XkbBell  without
	    first initializing the keyboard extension.

       True	      The  XkbDeviceBellEvent  sends an	XkbBellNotify event to
		      to all interested	clients	and returns True.

       False	      If a compatible keyboard extension isn't present in  the
		      X	server,	XkbDeviceBellEvent immediately returns False

       Xkb  generates  XkbBellNotify events for	all bells except for those re-
       sulting from
	      calls  to	 XkbForceDeviceBell  and  XkbForceBell.	  To   receive
	      XkbBellNotify   events   under  all  possible  conditions,  pass
	      XkbBellNotifyMask	in both	the bits_to_change and values_for_bits
	      parameters to XkbSelectEvents.

	      The  XkbBellNotify  event	has no event details. It is either se-
	      lected or	it is not.  However, you  can  call  XkbSelectEventDe-
	      tails  using  XkbBellNotify as the event_type and	specifying Xk-
	      bAllBellEventsMask in bits_to_change and values_for_bits.	  This
	      has the same effect as a call to XkbSelectEvents.

	      The structure for	the XkbBellNotify event	type contains:

		 typedef struct	_XkbBellNotify {
		     int	    type;	 /* Xkb	extension base event code */
		     unsigned long  serial;	 /* X server serial number for event */
		     Bool	    send_event;	 /* True => synthetically generated */
		     Display *	    display;	 /* server connection where event generated */
		     Time	    time;	 /* server time	when event generated */
		     int	    xkb_type;	 /* XkbBellNotify */
		     unsigned int   device;	 /* Xkb	device ID, will	not be XkbUseCoreKbd */
		     int	    percent;	 /* requested volume as	% of max */
		     int	    pitch;	 /* requested pitch in Hz */
		     int	    duration;	 /* requested duration in microseconds */
		     unsigned int   bell_class;	 /* X input extension feedback class */
		     unsigned int   bell_id;	 /* X input extension feedback ID */
		     Atom	    name;	 /* "name" of requested	bell */
		     Window	    window;	 /* window associated with event */
		     Bool	    event_only;	 /* False -> the server	did not	produce	a beep */
		 } XkbBellNotifyEvent;

	      If  your	application  needs to generate visual bell feedback on
	      the screen when it receives a bell event,	use the	window	ID  in
	      the XkbBellNotifyEvent, if present.

       XBell(3),   XkbBellNotify(3),  XkbChangeEnabledControls(3),  XkbDevice-
       Bell(3),	 XkbForceBell(3),  XkbForceDeviceBell(3),  XkbSelectEvents(3),
       XkbSelectEventDetails(3), XkbUseCoreKbd(3)

X Version 11			 libX11	1.7.2		 XkbDeviceBellEvent(3)


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