XChangeKeyboardControl(XS) 6 January 1993 XChangeKeyboardControl(XS)
X Version 11 (Release 5)
Name
XChangeKeyboardControl - manipulate keyboard settings and keyboard
control structure
Syntax
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
display Specifies the connection to the X server.
keysreturn Returns an array of bytes that identifies which keys are
pressed down. Each bit represents one key of the key-
board.
percent Specifies the volume for the bell, which can range from
-100 to 100 inclusive.
valuemask Specifies which controls to change. This mask is the bit-
wise inclusive OR of the valid control mask bits.
values Specifies one value for each bit set to 1 in the mask.
valuesreturn Returns the current keyboard controls in the specified
XKeyboardState structure.
Description
The XChangeKeyboardControl function controls the keyboard characteristics
defined by the XKeyboardControl structure. The valuemask 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 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 (1q<<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 keyclickpercent 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 bellpercent 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 bellpitch
member sets the pitch (specified in Hz) of the bell, if possible. A set-
ting of -1 restores the default. Other negative values generate a ``Bad-
Value'' error. The bellduration 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 ledmode and led members are specified, the state of that LED
is changed, if possible. The ledmode member can be set to LedModeOn or
LedModeOff. If only ledmode 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 ledmode, a ``BadMatch'' error results.
If both the autorepeatmode and key members are specified, the
autorepeatmode of that key is changed (according to AutoRepeatModeOn,
AutoRepeatModeOff, or AutoRepeatModeDefault), if possible. If only
autorepeatmode is specified, the global autorepeatmode for the entire
keyboard is changed, if possible, and does not affect the per key set-
tings. If a key is specified without an autorepeatmode, 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 AutoRepeatMo-
deOn, 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 ledmask corresponds to LED
one, and each bit set to 1 in ledmask indicates an LED that is lit. The
globalautorepeat member can be set to AutoRepeatModeOn or AutoRepeat-
ModeOff. The autorepeats 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(XS), XSetPointerMapping(XS)
Xlib - C Language X Interface