1XkbForceDeviceBell(3) XKB FUNCTIONS XkbForceDeviceBell(3)
2
6 XkbForceDeviceBell - Rings the bell on any keyboard, overriding user
7 preference settings for audible bells
8
10 Bool XkbForceDeviceBell (Display *display, Window window, unsigned int
11 device_spec, unsigned int bell_class, unsigned int bell_id, int
12 percent);
13
15 - display
16 connection to the X server
17 - window
19 event window, or None
20 - device_spec
22 device ID, or XkbUseCoreKbd
23 - bell_class
25 input extension class of the bell to be rung
26 - bell_id
28 input extension ID of the bell to be rung
29 - percent
31 relative volume, which can range from -100 to 100 inclusive
32
34 The core X protocol allows only applications to explicitly sound the
35 system bell with a given duration, pitch, and volume. Xkb extends this
36 capability by allowing clients to attach symbolic names to bells, dis‐
37 able audible bells, and receive an event whenever the keyboard bell is
38 rung. For the purposes of this document, the audible bell is defined to
39 be the system bell, or the default keyboard bell, as opposed to any
40 other audible sound generated elsewhere in the system. You can ask to
41 receive XkbBellNotify events when any client rings any one of the fol‐
42 lowing:
43 · The default bell
46 · Any bell on an input device that can be specified by a bell_class
48 and bell_id pair
49 · Any bell specified only by an arbitrary name. (This is, from the
51 server's point of view, merely a name, and not connected with any
52 physical sound-generating device. Some client application must
53 generate the sound, or visual feedback, if any, that is associated
54 with the name.)
55 You can also ask to receive XkbBellNotify events when the server rings
58 the default bell or if any client has requested events only (without
59 the bell sounding) for any of the bell types previously listed.
60 You can disable audible bells on a global basis. For example, a client
62 that replaces the keyboard bell with some other audible cue might want
63 to turn off the AudibleBell control to prevent the server from also
64 generating a sound and avoid cacophony. If you disable audible bells
65 and request to receive XkbBellNotify events, you can generate feedback
66 different from the default bell.
67 You can, however, override the AudibleBell control by calling one of
69 the functions that force the ringing of a bell in spite of the setting
70 of the AudibleBell control - XkbForceDeviceBell or XkbForceBell. In
71 this case the server does not generate a bell event.
72 Just as some keyboards can produce keyclicks to indicate when a key is
74 pressed or repeating, Xkb can provide feedback for the controls by
75 using special beep codes. The AccessXFeedback control is used to con‐
76 figure the specific types of operations that generate feedback.
77 Bell Names
79 You can associate a name to an act of ringing a bell by converting the
81 name to an Atom and then using this name when you call the functions
82 listed in this chapter. If an event is generated as a result, the name
83 is then passed to all other clients interested in receiving XkbBellNo‐
84 tify events. Note that these are arbitrary names and that there is no
85 binding to any sounds. Any sounds or other effects (such as visual
86 bells on the screen) must be generated by a client application upon
87 receipt of the bell event containing the name. There is no default name
88 for the default keyboard bell. The server does generate some predefined
89 bells for the AccessX controls. These named bells are shown in Table 1;
90 the name is included in any bell event sent to clients that have
91 requested to receive XkbBellNotify events.
92 Table 1 Predefined Bells
95 ──────────────────────────────────────────────────────────────
96 Action Named Bell
97 ──────────────────────────────────────────────────────────────
98 Indicator turned on AX_IndicatorOn
99 Indicator turned off AX_IndicatorOff
100 More than one indicator changed state AX_IndicatorChange
101 Control turned on AX_FeatureOn
102 Control turned off AX_FeatureOff
103 More than one control changed state AX_FeatureChange
104 SlowKeys and BounceKeys about to be AX_SlowKeysWarning
105 turned on or off
106 SlowKeys key pressed AX_SlowKeyPress
107 SlowKeys key accepted AX_SlowKeyAccept
108 SlowKeys key rejected AX_SlowKeyReject
109 Accepted SlowKeys key released AX_SlowKeyRelease
110 BounceKeys key rejected AX_BounceKeyReject
111 StickyKeys key latched AX_StickyLatch
112 StickyKeys key locked AX_StickyLock
113 StickyKeys key unlocked AX_StickyUnlock
114 Audible Bells
116 Using Xkb you can generate bell events that do not necessarily ring the
118 system bell. This is useful if you need to use an audio server instead
119 of the system beep. For example, when an audio client starts, it could
120 disable the audible bell (the system bell) and then listen for XkbBell‐
121 Notify events. When it receives a XkbBellNotify event, the audio client
122 could then send a request to an audio server to play a sound.
123 You can control the audible bells feature by passing the XkbAudible‐
125 BellMask to XkbChangeEnabledControls. If you set XkbAudibleBellMask
126 on, the server rings the system bell when a bell event occurs. This is
127 the default. If you set XkbAudibleBellMask off and a bell event occurs,
128 the server does not ring the system bell unless you call XkbForceDe‐
129 viceBell or XkbForceBell.
130 Audible bells are also part of the per-client auto-reset controls.
132 Bell Functions
134 Use the functions described in this section to ring bells and to gener‐
136 ate bell events.
137 The input extension has two types of feedbacks that can generate bells
139 - bell feedback and keyboard feedback. Some of the functions in this
140 section have bell_class and bell_id parameters; set them as follows:
141 Set bell_class to BellFeedbackClass or KbdFeedbackClass. A device can
142 have more than one feedback of each type; set bell_id to the particular
143 bell feedback of bell_class type.
144 Table 2 shows the conditions that cause a bell to sound or an XkbBell‐
146 NotifyEvent to be generated when a bell function is called.
147 Table 2 Bell Sounding and Bell Event Generating
150 ───────────────────────────────────────────────────────────────────────────
151 Function called AudibleBell Server sounds a bell Server sends an
152 XkbBellNotifyEvent
153 ───────────────────────────────────────────────────────────────────────────
154 XkbDeviceBell On Yes Yes
155 XkbDeviceBell Off No Yes
156 XkbBell On Yes Yes
157 XkbBell Off No Yes
158 XkbDeviceBellEvent On or Off No Yes
159 XkbBellEvent On or Off No Yes
160 XkbDeviceForceBell On or Off Yes No
161 XkbForceBell On or Off Yes No
162 If a compatible keyboard extension isn't present in the X server, Xkb‐
165 ForceDeviceBell immediately returns False. Otherwise, XkbForceDevice‐
166 Bell rings the bell as specified for the display and keyboard device
167 and returns True. Set percent to be the volume relative to the base
168 volume for the keyboard as described for XBell.
169 There is no name parameter because XkbForceDeviceBell does not cause an
171 XkbBellNotify event.
172 You can call XkbBell without first initializing the keyboard extension.
174
176 Xkb generates XkbBellNotify events for all bells except for those
177 resulting from calls to XkbForceDeviceBell and XkbForceBell. To
178 receive XkbBellNotify events under all possible conditions, pass
179 XkbBellNotifyMask in both the bits_to_change and values_for_bits param‐
180 eters to XkbSelectEvents.
181 The XkbBellNotify event has no event details. It is either selected or
183 it is not. However, you can call XkbSelectEventDetails using XkbBell‐
184 Notify as the event_type and specifying XkbAllBellNotifyMask in
185 bits_to_change and values_for_bits. This has the same effect as a call
186 to XkbSelectEvents.
187 The structure for the XkbBellNotify event type contains:
189 typedef struct _XkbBellNotify {
191 int type; /∗ Xkb extension base event code */
192 unsigned long serial; /∗ X server serial number for event */
193 Bool send_event; /∗ True => synthetically generated */
194 Display * display; /∗ server connection where event generated */
195 Time time; /∗ server time when event generated */
196 int xkb_type; /∗ XkbBellNotify */
197 unsigned int device; /∗ Xkb device ID, will not be XkbUseCoreKbd */
198 int percent; /∗ requested volume as % of max */
199 int pitch; /∗ requested pitch in Hz */
200 int duration; /∗ requested duration in microseconds */
201 unsigned int bell_class; /∗ X input extension feedback class */
202 unsigned int bell_id; /∗ X input extension feedback ID */
203 Atom name; /∗ "name" of requested bell */
204 Window window; /∗ window associated with event */
205 Bool event_only; /∗ False -> the server did not produce a beep */
206 } XkbBellNotifyEvent;
207 If your application needs to generate visual bell feedback on the
209 screen when it receives a bell event, use the window ID in the XkbBell‐
210 NotifyEvent, if present.
211
213 XBell(3), XkbBell(3), XkbBellNotify(3), XkbChangeEnabledControls(3),
214 XkbDeviceBell(3), XkbForceBell(3), XkbForceDeviceBell(3), XkbSe‐
215 lectEventDetails(3), XkbSelectEvents(3)
216X Version 11 libX11 1.3.4 XkbForceDeviceBell(3)