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     X Version 11 (1 September 1988)   XChangeKeyboardControl(XS)



     NAME
          XChangeKeyboardControl, XGetKeyboardControl, XAutoRepeatOn,
          XAutoRepeatOff, XBell, XQueryKeymap - manipulate keyboard
          settings


     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.

          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 one value for each bit set to 1 in the
                    mask.

          values    Specifies which controls to change.  This mask is
                    the bitwise inclusive OR of the valid control mask
                    bits.

          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.


     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


     (printed 2/12/90) (1 September 1988)hangeKeyboardControl(XS)

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026