XChangeKeyboardControl(3X11)XChangeKeyboardControl(3X11)NAME
XChangeKeyboardControl, XGetKeyboardControl, XAutoRepeatOn, XAutoRe‐
peatOff, XBell, XQueryKeymap, XKeyboardControl - manipulate keyboard
settings and keyboard control structure
SYNOPSIS
XChangeKeyboardControl(display, value_mask, values)
Display *display;
unsigned long value_mask;
XKeyboardControl *values;
XGetKeyboardControl(display, values_return)
Display *display;
XKeyboardState *values_return;
XAutoRepeatOn(display)
Display *display;
XAutoRepeatOff(display)
Display *display;
XBell(display, percent)
Display *display;
int percent;
XQueryKeymap(display, keys_return)
Display *display;
char keys_return[32];
ARGUMENTS
Specifies the connection to the X server. Returns an array of bytes
that identifies which keys are pressed down. Each bit represents one
key of the keyboard. Specifies the volume for the bell, which can
range from -100 to 100 inclusive. Specifies which controls to change.
This mask is the bitwise inclusive OR of the valid control mask bits.
Specifies one value for each bit set to 1 in the mask. Returns the
current keyboard controls in the specified XKeyboardState structure.
DESCRIPTION
The XChangeKeyboardControl function controls the keyboard characteris‐
tics defined by the XKeyboardControl structure. The value_mask argument
specifies which values are to be changed.
XChangeKeyboardControl can generate BadMatch and BadValue errors.
The XGetKeyboardControl function returns the current control values for
the keyboard to the XKeyboardState structure.
The XAutoRepeatOn function turns on auto-repeat for the keyboard 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 dis‐
play, 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 nega‐
tive is:
base + [(base * percent) / 100]
To change the base volume of the bell, use XChangeKeyboardControl.
XBell can generate a BadValue error.
The XQueryKeymap function returns a bit vector for the logical 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 applica‐
tions) 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 */
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 */ } XKey‐
boardControl;
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 BadValue error. The
bell_pitch member sets the pitch (specified in Hz) of the bell, if pos‐
sible. A setting of -1 restores the default. Other negative values gen‐
erate 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 BadValue 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 LedMod‐
eOn 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 sup‐
ported. No standard interpretation of LEDs is defined. If led is speci‐
fied 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 AutoRepeatModeDefault), 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 settings. If a key is specified without an auto_repeat_mode, a Bad‐
Match 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 AutoRepeatMod‐
eOn, keys should obey their individual auto-repeat modes. When global
mode is AutoRepeatModeOff, no keys should auto-repeat. An auto-repeat‐
ing key generates alternating KeyPress and KeyRelease events. When a
key is used as a modifier, it is 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 AutoRe‐
peatModeOff. The auto_repeats member is a bit vector. Each bit set to 1
indicates that auto-repeat is enabled for the corresponding key. 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 repre‐
senting key 8N.
DIAGNOSTICS
Some argument or pair of arguments has the correct type and range but
fails to match in some other way required by the request. 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 generate this error.
SEE ALSOXChangeKeyboardMapping(3X11), XSetPointerMapping(3X11)
Xlib -- C Language X Interface
XChangeKeyboardControl(3X11)
