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 event window, or None
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17 percent
18 relative volume, which can range from -100 to 100 inclusive
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20 name a bell name, or NULL
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23 The core X protocol allows only applications to explicitly sound the
24 system bell with a given duration, pitch, and volume. Xkb extends this
25 capability by allowing clients to attach symbolic names to bells, dis‐
26 able audible bells, and receive an event whenever the keyboard bell is
27 rung. For the purposes of this document, the audible bell is defined to
28 be the system bell, or the default keyboard bell, as opposed to any
29 other audible sound generated elsewhere in the system. You can ask to
30 receive XkbBellNotify events when any client rings any one of the fol‐
31 lowing:
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34 • The default bell
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36 • Any bell on an input device that can be specified by a bell_class
37 and bell_id pair
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39 • Any bell specified only by an arbitrary name. (This is, from the
40 server's point of view, merely a name, and not connected with any
41 physical sound-generating device. Some client application must
42 generate the sound, or visual feedback, if any, that is associated
43 with the name.)
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46 You can also ask to receive XkbBellNotify events when the server rings
47 the default bell or if any client has requested events only (without
48 the bell sounding) for any of the bell types previously listed.
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50 You can disable audible bells on a global basis. For example, a client
51 that replaces the keyboard bell with some other audible cue might want
52 to turn off the AudibleBell control to prevent the server from also
53 generating a sound and avoid cacophony. If you disable audible bells
54 and request to receive XkbBellNotify events, you can generate feedback
55 different from the default bell.
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57 You can, however, override the AudibleBell control by calling one of
58 the functions that force the ringing of a bell in spite of the setting
59 of the AudibleBell control - XkbForceDeviceBell or XkbForceBell. In
60 this case the server does not generate a bell event.
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62 Just as some keyboards can produce keyclicks to indicate when a key is
63 pressed or repeating, Xkb can provide feedback for the controls by us‐
64 ing special beep codes. The AccessXFeedback control is used to config‐
65 ure the specific types of operations that generate feedback.
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67 Bell Names
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69 You can associate a name to an act of ringing a bell by converting the
70 name to an Atom and then using this name when you call the functions
71 listed in this chapter. If an event is generated as a result, the name
72 is then passed to all other clients interested in receiving XkbBellNo‐
73 tify events. Note that these are arbitrary names and that there is no
74 binding to any sounds. Any sounds or other effects (such as visual
75 bells on the screen) must be generated by a client application upon re‐
76 ceipt of the bell event containing the name. There is no default name
77 for the default keyboard bell. The server does generate some predefined
78 bells for the AccessX controls. These named bells are shown in Table 1
79 below; the name is included in any bell event sent to clients that have
80 requested to receive XkbBellNotify events.
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83 Table 1 Predefined Bells
84 ──────────────────────────────────────────────────────────────────────────
85 Action Named Bell
86 ──────────────────────────────────────────────────────────────────────────
87 Indicator turned on AX_IndicatorOn
88 Indicator turned off AX_IndicatorOff
89 More than one indicator changed state AX_IndicatorChange
90 Control turned on AX_FeatureOn
91 Control turned off AX_FeatureOff
92 More than one control changed state AX_FeatureChange
93 SlowKeys and BounceKeys about to be turned on or off AX_SlowKeysWarning
94 SlowKeys key pressed AX_SlowKeyPress
95 SlowKeys key accepted AX_SlowKeyAccept
96 SlowKeys key rejected AX_SlowKeyReject
97 Accepted SlowKeys key released AX_SlowKeyRelease
98 BounceKeys key rejected AX_BounceKeyReject
99 StickyKeys key latched AX_StickyLatch
100 StickyKeys key locked AX_StickyLock
101 StickyKeys key unlocked AX_StickyUnlock
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103 Audible Bells
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105 Using Xkb you can generate bell events that do not necessarily ring the
106 system bell. This is useful if you need to use an audio server instead
107 of the system beep. For example, when an audio client starts, it could
108 disable the audible bell (the system bell) and then listen for XkbBell‐
109 Notify events. When it receives a XkbBellNotify event, the audio client
110 could then send a request to an audio server to play a sound.
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112 You can control the audible bells feature by passing the XkbAudible‐
113 BellMask to XkbChangeEnabledControls. If you set XkbAudibleBellMask
114 on, the server rings the system bell when a bell event occurs. This is
115 the default. If you set XkbAudibleBellMask off and a bell event occurs,
116 the server does not ring the system bell unless you call XkbForceDe‐
117 viceBell or XkbForceBell.
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119 Audible bells are also part of the per-client auto-reset controls.
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121 Bell Functions
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123 Use the functions described in this section to ring bells and to gener‐
124 ate bell events.
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126 The input extension has two types of feedbacks that can generate bells
127 - bell feedback and keyboard feedback. Some of the functions in this
128 section have bell_class and bell_id parameters; set them as follows:
129 Set bell_class to BellFeedbackClass or KbdFeedbackClass. A device can
130 have more than one feedback of each type; set bell_id to the particular
131 bell feedback of bell_class type.
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133 Table 2 shows the conditions that cause a bell to sound or an XkbBell‐
134 NotifyEvent to be generated when a bell function is called.
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137 Table 2 Bell Sounding and Bell Event Generating
138 ───────────────────────────────────────────────────────────────────────────
139 Function called AudibleBell Server sounds a bell Server sends an
140 XkbBellNotifyEvent
141 ───────────────────────────────────────────────────────────────────────────
142 XkbDeviceBell On Yes Yes
143 XkbDeviceBell Off No Yes
144 XkbBell On Yes Yes
145 XkbBell Off No Yes
146 XkbDeviceBellEvent On or Off No Yes
147 XkbBellEvent On or Off No Yes
148 XkbDeviceForceBell On or Off Yes No
149 XkbForceBell On or Off Yes No
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151 If a compatible keyboard extension isn't present in the X server,
152 XkbBell calls XBell with the specified display and percent, and returns
153 False. Otherwise, XkbBell calls XkbDeviceBell with the specified dis‐
154 play, window, percent, and name, a device_spec of XkbUseCoreKbd, a
155 bell_class of XkbDfltXIClass, and a bell_id of XkbDfltXIId, and returns
156 True.
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158 If you have disabled the audible bell, the server does not ring the
159 system bell, although it does generate a XkbBellNotify event.
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161 You can call XkbBell without first initializing the keyboard extension.
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164 FALSE The XkbBell function returns FALSE if XlibDisplayNoXkb
165 is set.
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168 Xkb generates XkbBellNotify events for all bells except for those re‐
169 sulting from calls to XkbForceDeviceBell and XkbForceBell. To receive
170 XkbBellNotify events under all possible conditions, pass XkbBellNotify‐
171 Mask in both the bits_to_change and values_for_bits parameters to XkbS‐
172 electEvents.
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174 The XkbBellNotify event has no event details. It is either selected or
175 it is not. However, you can call XkbSelectEventDetails using XkbBell‐
176 Notify as the event_type and specifying XkbAllBellEventsMask in
177 bits_to_change and values_for_bits. This has the same effect as a call
178 to XkbSelectEvents.
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180 The structure for the XkbBellNotify event type contains:
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182 typedef struct _XkbBellNotify {
183 int type; /* Xkb extension base event code */
184 unsigned long serial; /* X server serial number for event */
185 Bool send_event; /* True => synthetically generated */
186 Display * display; /* server connection where event generated */
187 Time time; /* server time when event generated */
188 int xkb_type; /* XkbBellNotify */
189 unsigned int device; /* Xkb device ID, will not be XkbUseCoreKbd */
190 int percent; /* requested volume as % of max */
191 int pitch; /* requested pitch in Hz */
192 int duration; /* requested duration in microseconds */
193 unsigned int bell_class; /* X input extension feedback class */
194 unsigned int bell_id; /* X input extension feedback ID */
195 Atom name; /* "name" of requested bell */
196 Window window; /* window associated with event */
197 Bool event_only; /* False -> the server did not produce a beep */
198 } XkbBellNotifyEvent;
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200 If your application needs to generate visual bell feedback on the
201 screen when it receives a bell event, use the window ID in the XkbBell‐
202 NotifyEvent, if present.
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206 XBell(3), XkbBellNotify(3), XkbChangeEnabledControls(3), XkbDevice‐
207 Bell(3), XkbForceBell(3), XkbForceDeviceBell(3), XkbUseCoreKbd(3)
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216X Version 11 libX11 1.8.7 XkbBell(3)