XkbBellEvent - Man Page

Provides a function that initiates a bell event for the keyboard without ringing the bell

Synopsis

Bool XkbBellEvent (Display *display, Window window, int percent, Atom name);

Arguments

display

connection to the X server

window

the event window, or None

percent

relative volume, which can range from -100 to 100 inclusive

name

a bell name, or NULL

Description

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, disable 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  following:

Return Values

False

The XkbBellEvent immediately returns False, if a compatible keyboard extension isn't present in  the X server.

Structures

Xkb generates XkbBellNotify events for all bells except for those resulting 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 selected or it is  not.  However, you can call XkbSelectEventDetails using XkbBellNotify as the event_type and specifying XkbAllBellEventsMask 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.

See Also

XkbChangeEnabledControls(3), XkbDeviceBellEvent(3), XkbForceBell(3), XkbForceDeviceBell(3), XkbSelectEventDetails(3), XkbSelectEvents(3)

Info

libX11 1.8.10 X Version 11 XKB FUNCTIONS