XChangeKeyboardControl(3X1XLIB FUNCTIXChangeKeyboardControl(3X11)
NAME
XChangeKeyboardControl, XGetKeyboardControl, XAutoRepeatOn,
XAutoRepeatOff, XBell, XQueryKeymap, XKeyboardControl -
manipulate keyboard settings and keyboard control structure
SYNTAX
int XChangeKeyboardControl(Display *display, unsigned long
value_mask, XKeyBoardControl *values);
int XGetKeyboardControl(Display *display, XKeyBoardState
*values_return);
int XAutoRepeatOn(Display *display);
int XAutoRepeatOff(Display *display);
int XBell(Display *display, int percent);
int XQueryKeymap(Display *display, char keys_return[32]);
ARGUMENTS
display Specifies the connection to the X server.
keys_return
Returns an array of bytes that identifies which
keys are pressed down. Each bit represents one key
of the keyboard.
percent Specifies the volume for the bell, which can range
from -100 to 100 inclusive.
value_mask
Specifies which controls to change. This mask is
the bitwise inclusive OR of the valid control mask
bits.
values Specifies one value for each bit set to 1 in the
mask.
values_return
Returns the current keyboard controls in the
specified XKeyboardState structure.
DESCRIPTION
The XChangeKeyboardControl function controls the keyboard
characteristics defined by the XKeyboardControl structure.
The value_mask argument specifies which values are to be
changed.
XChangeKeyboardControl can generate BadMatch and BadValue
errors.
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The XGetKeyboardControl function returns the current control
values for the keyboard to the XKeyboardState structure.
The XAutoRepeatOn function turns on auto-repeat for the key-
board on the specified display.
The XAutoRepeatOff function turns off auto-repeat for the
keyboard on the specified display.
The XBell function rings the bell on the keyboard on the
specified display, if possible. The specified volume is
relative to the base volume for the keyboard. If the value
for the percent argument is not in the range -100 to 100
inclusive, a BadValue error results. The volume at which the
bell rings when the percent argument is nonnegative is:
base - [(base * percent) / 100] + percent
The volume at which the bell rings when the percent argument
is negative is:
base + [(base * percent) / 100]
To change the base volume of the bell, use XChangeKeyboard-
Control.
XBell can generate a BadValue error.
The XQueryKeymap function returns a bit vector for the logi-
cal state of the keyboard, where each bit set to 1 indicates
that the corresponding key is currently pressed down. The
vector is represented as 32 bytes. Byte N (from 0) contains
the bits for keys 8N to 8N + 7 with the least significant
bit in the byte representing key 8N.
Note that the logical state of a device (as seen by client
applications) may lag the physical state if device event
processing is frozen.
STRUCTURES
The XKeyboardControl structure contains:
/* Mask bits for ChangeKeyboardControl */
#define KBKeyClickPercent (1L<<0)
#define KBBellPercent (1L<<1)
#define KBBellPitch (1L<<2)
#define KBBellDuration (1L<<3)
#define KBLed (1L<<4)
#define KBLedMode (1L<<5)
#define KBKey (1L<<6)
#define KBAutoRepeatMode (1L<<7)
/* Values */
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typedef struct {
int key_click_percent;
int bell_percent;
int bell_pitch;
int bell_duration;
int led;
int led_mode; /* LedModeOn, LedModeOff */
int key;
int auto_repeat_mode;/* AutoRepeatModeOff, AutoRepeatModeOn,
AutoRepeatModeDefault */
} XKeyboardControl;
The key_click_percent member sets the volume for key clicks
between 0 (off) and 100 (loud) inclusive, if possible. A
setting of -1 restores the default. Other negative values
generate a BadValue error.
The bell_percent sets the base volume for the bell between 0
(off) and 100 (loud) inclusive, if possible. A setting of -1
restores the default. Other negative values generate a Bad-
Value error. The bell_pitch member sets the pitch (specified
in Hz) of the bell, if possible. A setting of -1 restores
the default. Other negative values generate a BadValue
error. The bell_duration member sets the duration of the
bell specified in milliseconds, if possible. A setting of -1
restores the default. Other negative values generate a Bad-
Value error.
If both the led_mode and led members are specified, the
state of that LED is changed, if possible. The led_mode
member can be set to LedModeOn or LedModeOff. If only
led_mode is specified, the state of all LEDs are changed, if
possible. At most 32 LEDs numbered from one are supported.
No standard interpretation of LEDs is defined. If led is
specified without led_mode, a BadMatch error results.
If both the auto_repeat_mode and key members are specified,
the auto_repeat_mode of that key is changed (according to
AutoRepeatModeOn, AutoRepeatModeOff, or AutoRepeatModeDe-
fault), if possible. If only auto_repeat_mode is specified,
the global auto_repeat_mode for the entire keyboard is
changed, if possible, and does not affect the per-key set-
tings. If a key is specified without an auto_repeat_mode, a
BadMatch error results. Each key has an individual mode of
whether or not it should auto-repeat and a default setting
for the mode. In addition, there is a global mode of whether
auto-repeat should be enabled or not and a default setting
for that mode. When global mode is AutoRepeatModeOn, keys
should obey their individual auto-repeat modes. When global
mode is AutoRepeatModeOff, no keys should auto-repeat. An
auto-repeating key generates alternating KeyPress and
KeyRelease events. When a key is used as a modifier, it is
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desirable for the key not to auto-repeat, regardless of its
auto-repeat setting.
The XKeyboardState structure contains:
typedef struct {
int key_click_percent;
int bell_percent;
unsigned int bell_pitch, bell_duration;
unsigned long led_mask;
int global_auto_repeat;
char auto_repeats[32];
} XKeyboardState;
For the LEDs, the least significant bit of led_mask
corresponds to LED one, and each bit set to 1 in led_mask
indicates an LED that is lit. The global_auto_repeat member
can be set to AutoRepeatModeOn or AutoRepeatModeOff. The
auto_repeats member is a bit vector. Each bit set to 1 indi-
cates that auto-repeat is enabled for the corresponding key.
The vector is represented as 32 bytes. Byte N (from 0) con-
tains the bits for keys 8N to 8N + 7 with the least signifi-
cant bit in the byte representing key 8N.
DIAGNOSTICS
BadMatch Some argument or pair of arguments has the correct
type and range but fails to match in some other
way required by the request.
BadValue Some numeric value falls outside the range of
values accepted by the request. Unless a specific
range is specified for an argument, the full range
defined by the argument's type is accepted. Any
argument defined as a set of alternatives can gen-
erate this error.
SEE ALSO
XChangeKeyboardMapping(3X11), XSetPointerMapping(3X11)
Xlib - C Language X Interface
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