1XkbForceBell(3) XKB FUNCTIONS XkbForceBell(3)
2
6 XkbForceBell - Overrides user preference settings for audible bells to
7 ring the bell on the default keyboard
8
10 Bool XkbForceBell (Display *display, int percent);
11
13 - display
14 connection to the X server
15 - percent
17 volume for the bell, which can range from -100 to 100 inclusive
18
20 The core X protocol allows only applications to explicitly sound the
21 system bell with a given duration, pitch, and volume. Xkb extends this
22 capability by allowing clients to attach symbolic names to bells, dis‐
23 able audible bells, and receive an event whenever the keyboard bell is
24 rung. For the purposes of this document, the audible bell is defined to
25 be the system bell, or the default keyboard bell, as opposed to any
26 other audible sound generated elsewhere in the system. You can ask to
27 receive XkbBellNotify events when any client rings any one of the fol‐
28 lowing:
29 • The default bell
32 • Any bell on an input device that can be specified by a bell_class
34 and bell_id pair
35 • Any bell specified only by an arbitrary name. (This is, from the
37 server's point of view, merely a name, and not connected with any
38 physical sound-generating device. Some client application must
39 generate the sound, or visual feedback, if any, that is associated
40 with the name.)
41 You can also ask to receive XkbBellNotify events when the server rings
44 the default bell or if any client has requested events only (without
45 the bell sounding) for any of the bell types previously listed.
46 You can disable audible bells on a global basis. For example, a client
48 that replaces the keyboard bell with some other audible cue might want
49 to turn off the AudibleBell control to prevent the server from also
50 generating a sound and avoid cacophony. If you disable audible bells
51 and request to receive XkbBellNotify events, you can generate feedback
52 different from the default bell.
53 You can, however, override the AudibleBell control by calling one of
55 the functions that force the ringing of a bell in spite of the setting
56 of the AudibleBell control - XkbForceDeviceBell or XkbForceBell. In
57 this case the server does not generate a bell event.
58 Just as some keyboards can produce keyclicks to indicate when a key is
60 pressed or repeating, Xkb can provide feedback for the controls by us‐
61 ing special beep codes. The AccessXFeedback control is used to config‐
62 ure the specific types of operations that generate feedback.
63 Bell Names
65 You can associate a name to an act of ringing a bell by converting the
67 name to an Atom and then using this name when you call the functions
68 listed in this chapter. If an event is generated as a result, the name
69 is then passed to all other clients interested in receiving XkbBellNo‐
70 tify events. Note that these are arbitrary names and that there is no
71 binding to any sounds. Any sounds or other effects (such as visual
72 bells on the screen) must be generated by a client application upon re‐
73 ceipt of the bell event containing the name. There is no default name
74 for the default keyboard bell. The server does generate some predefined
75 bells for the AccessX controls. These named bells are shown in the Ta‐
76 ble 1; the name is included in any bell event sent to clients that have
77 requested to receive XkbBellNotify events.
78 Table 1 Predefined Bells
81 ──────────────────────────────────────────────────────────────
82 Action Named Bell
83 ──────────────────────────────────────────────────────────────
84 Indicator turned on AX_IndicatorOn
85 Indicator turned off AX_IndicatorOff
86 More than one indicator changed state AX_IndicatorChange
87 Control turned on AX_FeatureOn
88 Control turned off AX_FeatureOff
89 More than one control changed state AX_FeatureChange
90 SlowKeys and BounceKeys about to be AX_SlowKeysWarning
91 turned on or off
92 SlowKeys key pressed AX_SlowKeyPress
93 SlowKeys key accepted AX_SlowKeyAccept
94 SlowKeys key rejected AX_SlowKeyReject
95 Accepted SlowKeys key released AX_SlowKeyRelease
96 BounceKeys key rejected AX_BounceKeyReject
97 StickyKeys key latched AX_StickyLatch
98 StickyKeys key locked AX_StickyLock
99 StickyKeys key unlocked AX_StickyUnlock
100 Audible Bells
102 Using Xkb you can generate bell events that do not necessarily ring the
104 system bell. This is useful if you need to use an audio server instead
105 of the system beep. For example, when an audio client starts, it could
106 disable the audible bell (the system bell) and then listen for XkbBell‐
107 Notify events. When it receives a XkbBellNotify event, the audio client
108 could then send a request to an audio server to play a sound.
109 You can control the audible bells feature by passing the XkbAudible‐
111 BellMask to XkbChangeEnabledControls. If you set XkbAudibleBellMask
112 on, the server rings the system bell when a bell event occurs. This is
113 the default. If you set XkbAudibleBellMask off and a bell event occurs,
114 the server does not ring the system bell unless you call XkbForceDe‐
115 viceBell or XkbForceBell.
116 Audible bells are also part of the per-client auto-reset controls.
118 Bell Functions
120 Use the functions described in this section to ring bells and to gener‐
122 ate bell events.
123 The input extension has two types of feedbacks that can generate bells
125 - bell feedback and keyboard feedback. Some of the functions in this
126 section have bell_class and bell_id parameters; set them as follows:
127 Set bell_class to BellFeedbackClass or KbdFeedbackClass. A device can
128 have more than one feedback of each type; set bell_id to the particular
129 bell feedback of bell_class type.
130 Table 2 shows the conditions that cause a bell to sound or an XkbBell‐
132 NotifyEvent to be generated when a bell function is called.
133 Table 2 Bell Sounding and Bell Event Generating
136 ───────────────────────────────────────────────────────────────────────────
137 Function called AudibleBell Server sounds a bell Server sends an
138 XkbBellNotifyEvent
139 ───────────────────────────────────────────────────────────────────────────
140 XkbDeviceBell On Yes Yes
141 XkbDeviceBell Off No Yes
142 XkbBell On Yes Yes
143 XkbBell Off No Yes
144 XkbDeviceBellEvent On or Off No Yes
145 XkbBellEvent On or Off No Yes
146 XkbDeviceForceBell On or Off Yes No
147 XkbForceBell On or Off Yes No
148 If a compatible keyboard extension isn't present in the X server, Xkb‐
151 ForceBell calls XBell with the specified display and percent and re‐
152 turns False. Otherwise, XkbForceBell calls XkbForceDeviceBell with the
153 specified display and percent, device_spec =XkbUseCoreKbd, bell_class =
154 XkbDfltXIClass, bell_id = XkbDfltXIId, window = None, and name = NULL,
155 and returns what XkbForceDeviceBell returns.
156 XkbForceBell does not cause an XkbBellNotify event.
158 You can call XkbBell without first initializing the keyboard extension.
160
162 False The XkbForceBell function returns False when a compati‐
163 ble keyboard extension isn't present in the X server.
164
166 Xkb generates XkbBellNotify events for all bells except for those re‐
167 sulting from calls to XkbForceDeviceBell and XkbForceBell. To receive
168 XkbBellNotify events under all possible conditions, pass XkbBellNotify‐
169 Mask in both the bits_to_change and values_for_bits parameters to XkbS‐
170 electEvents.
171 The XkbBellNotify event has no event details. It is either selected or
173 it is not. However, you can call XkbSelectEventDetails using XkbBell‐
174 Notify as the event_type and specifying XkbAllBellEventsMask in
175 bits_to_change and values_for_bits. This has the same effect as a call
176 to XkbSelectEvents.
177 The structure for the XkbBellNotify event type contains:
179 typedef struct _XkbBellNotify {
181 int type; /∗ Xkb extension base event code */
182 unsigned long serial; /∗ X server serial number for event */
183 Bool send_event; /∗ True => synthetically generated */
184 Display * display; /∗ server connection where event generated */
185 Time time; /∗ server time when event generated */
186 int xkb_type; /∗ XkbBellNotify */
187 unsigned int device; /∗ Xkb device ID, will not be XkbUseCoreKbd */
188 int percent; /∗ requested volume as % of max */
189 int pitch; /∗ requested pitch in Hz */
190 int duration; /∗ requested duration in microseconds */
191 unsigned int bell_class; /∗ X input extension feedback class */
192 unsigned int bell_id; /∗ X input extension feedback ID */
193 Atom name; /∗ "name" of requested bell */
194 Window window; /∗ window associated with event */
195 Bool event_only; /∗ False -> the server did not produce a beep */
196 } XkbBellNotifyEvent;
197 If your application needs to generate visual bell feedback on the
199 screen when it receives a bell event, use the window ID in the XkbBell‐
200 NotifyEvent, if present.
201
204 XBell(3), XkbBell(3), XkbChangeEnabledControls(3), XkbForceDevice‐
205 Bell(3), XkbSelectEventDetails(3), XkbSelectEvents(3)
206X Version 11 libX11 1.7.0 XkbForceBell(3)