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.
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
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
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 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 */
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
BadValue 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
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
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
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
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 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 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 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 generate this error.
SEE ALSO
XChangeKeyboardMapping(3), XkbChangeEnabledControls(3), XkbBell(3),
XkbDeviceBell(3), XkbGetMap(3), XSetPointerMapping(3)
Xlib - C Language X Interface