1XkbBell(3) XKB FUNCTIONS XkbBell(3)
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6 XkbBell - Rings the bell on the default keyboard
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9 Bool XkbBell (Display *display, Window window, int percent, Atom name);
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12 - display
13 connection to the X server
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15 - window
16 event window, or None
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18 - percent
19 relative volume, which can range from -100 to 100 inclusive
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21 - name a bell name, or NULL
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24 The core X protocol allows only applications to explicitly sound the
25 system bell with a given duration, pitch, and volume. Xkb extends this
26 capability by allowing clients to attach symbolic names to bells, dis‐
27 able audible bells, and receive an event whenever the keyboard bell is
28 rung. For the purposes of this document, the audible bell is defined to
29 be the system bell, or the default keyboard bell, as opposed to any
30 other audible sound generated elsewhere in the system. You can ask to
31 receive XkbBellNotify events when any client rings any one of the fol‐
32 lowing:
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35 · The default bell
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37 · Any bell on an input device that can be specified by a bell_class
38 and bell_id pair
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40 · Any bell specified only by an arbitrary name. (This is, from the
41 server's point of view, merely a name, and not connected with any
42 physical sound-generating device. Some client application must
43 generate the sound, or visual feedback, if any, that is associated
44 with the name.)
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47 You can also ask to receive XkbBellNotify events when the server rings
48 the default bell or if any client has requested events only (without
49 the bell sounding) for any of the bell types previously listed.
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51 You can disable audible bells on a global basis. For example, a client
52 that replaces the keyboard bell with some other audible cue might want
53 to turn off the AudibleBell control to prevent the server from also
54 generating a sound and avoid cacophony. If you disable audible bells
55 and request to receive XkbBellNotify events, you can generate feedback
56 different from the default bell.
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58 You can, however, override the AudibleBell control by calling one of
59 the functions that force the ringing of a bell in spite of the setting
60 of the AudibleBell control - XkbForceDeviceBell or XkbForceBell. In
61 this case the server does not generate a bell event.
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63 Just as some keyboards can produce keyclicks to indicate when a key is
64 pressed or repeating, Xkb can provide feedback for the controls by
65 using special beep codes. The AccessXFeedback control is used to con‐
66 figure the specific types of operations that generate feedback.
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68 Bell Names
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70 You can associate a name to an act of ringing a bell by converting the
71 name to an Atom and then using this name when you call the functions
72 listed in this chapter. If an event is generated as a result, the name
73 is then passed to all other clients interested in receiving XkbBellNo‐
74 tify events. Note that these are arbitrary names and that there is no
75 binding to any sounds. Any sounds or other effects (such as visual
76 bells on the screen) must be generated by a client application upon
77 receipt of the bell event containing the name. There is no default name
78 for the default keyboard bell. The server does generate some predefined
79 bells for the AccessX controls. These named bells are shown in Table 1
80 below; the name is included in any bell event sent to clients that have
81 requested to receive XkbBellNotify events.
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84 Table 1 Predefined Bells
85 ─────────────────────────────────────────────────────────────────────────────
86 Action Named Bell
87 ─────────────────────────────────────────────────────────────────────────────
88 Indicator turned on AX_IndicatorOn
89 Indicator turned off AX_IndicatorOff
90 More than one indicator changed state AX_IndicatorChange
91 Control turned on AX_FeatureOn
92 Control turned off AX_FeatureOff
93 More than one control changed state AX_FeatureChange
94 T{ SlowKeys and BounceKeys about to be turned on or off
95 T} AX_SlowKeysWarning
96 SlowKeys key pressed AX_SlowKeyPress
97 SlowKeys key accepted AX_SlowKeyAccept
98 SlowKeys key rejected AX_SlowKeyReject
99 Accepted SlowKeys key released AX_SlowKeyRelease
100 BounceKeys key rejected AX_BounceKeyReject
101 StickyKeys key latched AX_StickyLatch
102 StickyKeys key locked AX_StickyLock
103 StickyKeys key unlocked AX_StickyUnlock
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105 Audible Bells
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107 Using Xkb you can generate bell events that do not necessarily ring the
108 system bell. This is useful if you need to use an audio server instead
109 of the system beep. For example, when an audio client starts, it could
110 disable the audible bell (the system bell) and then listen for XkbBell‐
111 Notify events. When it receives a XkbBellNotify event, the audio client
112 could then send a request to an audio server to play a sound.
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114 You can control the audible bells feature by passing the XkbAudible‐
115 BellMask to XkbChangeEnabledControls. If you set XkbAudibleBellMask
116 on, the server rings the system bell when a bell event occurs. This is
117 the default. If you set XkbAudibleBellMask off and a bell event occurs,
118 the server does not ring the system bell unless you call XkbForceDe‐
119 viceBell or XkbForceBell.
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121 Audible bells are also part of the per-client auto-reset controls.
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123 Bell Functions
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125 Use the functions described in this section to ring bells and to gener‐
126 ate bell events.
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128 The input extension has two types of feedbacks that can generate bells
129 - bell feedback and keyboard feedback. Some of the functions in this
130 section have bell_class and bell_id parameters; set them as follows:
131 Set bell_class to BellFeedbackClass or KbdFeedbackClass. A device can
132 have more than one feedback of each type; set bell_id to the particular
133 bell feedback of bell_class type.
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135 Table 2 shows the conditions that cause a bell to sound or an XkbBell‐
136 NotifyEvent to be generated when a bell function is called.
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139 Table 2 Bell Sounding and Bell Event Generating
140 ───────────────────────────────────────────────────────────────────────────
141 Function called AudibleBell Server sounds a bell Server sends an
142 XkbBellNotifyEvent
143 ───────────────────────────────────────────────────────────────────────────
144 XkbDeviceBell On Yes Yes
145 XkbDeviceBell Off No Yes
146 XkbBell On Yes Yes
147 XkbBell Off No Yes
148 XkbDeviceBellEvent On or Off No Yes
149 XkbBellEvent On or Off No Yes
150 XkbDeviceForceBell On or Off Yes No
151 XkbForceBell On or Off Yes No
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153 If a compatible keyboard extension isn't present in the X server,
154 XkbBell calls XBell with the specified display and percent, and returns
155 False. Otherwise, XkbBell calls XkbDeviceBell with the specified dis‐
156 play, window, percent, and name, a device_spec of XkbUseCoreKbd, a
157 bell_class of XkbDfltXIClass, and a bell_id of XkbDfltXIId, and returns
158 True.
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160 If you have disabled the audible bell, the server does not ring the
161 system bell, although it does generate a XkbBellNotify event.
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163 You can call XkbBell without first initializing the keyboard extension.
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166 FALSE The XkbBell function returns FALSE if XlibDisplayNoXkb
167 is set.
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170 Xkb generates XkbBellNotify events for all bells except for those
171 resulting from calls to XkbForceDeviceBell and XkbForceBell. To
172 receive XkbBellNotify events under all possible conditions, pass
173 XkbBellNotifyMask in both the bits_to_change and values_for_bits param‐
174 eters to XkbSelectEvents.
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176 The XkbBellNotify event has no event details. It is either selected or
177 it is not. However, you can call XkbSelectEventDetails using XkbBell‐
178 Notify as the event_type and specifying XkbAllBellNotifyMask in
179 bits_to_change and values_for_bits. This has the same effect as a call
180 to XkbSelectEvents.
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182 The structure for the XkbBellNotify event type contains:
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184 typedef struct _XkbBellNotify {
185 int type; /∗ Xkb extension base event code */
186 unsigned long serial; /∗ X server serial number for event */
187 Bool send_event; /∗ True => synthetically generated */
188 Display * display; /∗ server connection where event generated */
189 Time time; /∗ server time when event generated */
190 int xkb_type; /∗ XkbBellNotify */
191 unsigned int device; /∗ Xkb device ID, will not be XkbUseCoreKbd
192 */
193 int percent; /∗ requested volume as % of max */
194 int pitch; /∗ requested pitch in Hz */
195 int duration; /∗ requested duration in microseconds */
196 unsigned int bell_class; /∗ X input extension feedback class */
197 unsigned int bell_id; /∗ X input extension feedback ID */
198 Atom name; /∗ "name" of requested bell */
199 Window window; /∗ window associated with event */
200 Bool event_only; /∗ False -> the server did not produce a beep
201 */
202 } XkbBellNotifyEvent;
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204 If your application needs to generate visual bell feedback on the
205 screen when it receives a bell event, use the window ID in the XkbBell‐
206 NotifyEvent, if present.
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210 XBell(3), XkbBellNotify(3), XkbChangeEnabledControls(3), XkbDevice‐
211 Bell(3), XkbForceBell(3), XkbForceDeviceBell(3), XkbUseCoreKbd(3)
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220X Version 11 libX11 1.3.4 XkbBell(3)