XIGRABBUTTON(3)

NAME
XIGrabButton, XIUngrabButton, XIGrabKeycode, XIUngrabKeycode, XIGrabTouchBegin, XIUngrabTouchBegin - grab/ungrab buttons or keys

SYNOPSIS

#include <X11/extensions/XInput2.h>

int XIGrabButton( Display *display,
                  int deviceid,
                  int button,
                  Window grab_window,
                  Cursor cursor,
                  int grab_mode,
                  int paired_device_mode,
                  Bool owner_events,
                  XIEventMask *mask,
                  int num_modifiers,
                  XIGrabModifiers *modifiers_inout);

int XIUngrabButton( Display *display,
                    int deviceid,
                    int button,
                    Window grab_window,
                    int num_modifiers,
                    XIGrabModifiers *modifiers);

int XIGrabKeycode( Display *display,
                   int deviceid,
                   int keycode,
                   Window grab_window,
                   int grab_mode,
                   int paired_device_mode,
                   Bool owner_events,
                   XIEventMask *mask,
                   int num_modifiers,
                   XIGrabModifiers *modifiers_inout);

int XIUngrabKeycode( Display *display,
                     int deviceid,
                     int keycode,
                     Window grab_window,
                     int num_modifiers,
                     XIGrabModifiers *modifiers);

int XIGrabTouchBegin( Display *display,
                      int deviceid,
                      Window grab_window,
                      Bool owner_events,
                      XIEventMask *mask,
                      int num_modifiers,
                      XIGrabModifiers *modifiers_inout);

int XIUngrabTouchBegin( Display *display,
                        int deviceid,
                        Window grab_window,
                        int num_modifiers,
                        XIGrabModifiers *modifiers);

display
       Specifies the connection to the X server.

device
       Specifies the device that is to be grabbed or released

button
       Specifies the device button that is to be grabbed or
       released or XIAnyButton.

keycode
       Specifies the keycode that is to be grabbed or released
       or XIAnyKeycode.

num_modifiers
       Number of elements in modifiers or modifiers_inout.

modifiers
       Specifies the set of latched and base modifiers or
       XIAnyModifier to ungrab. The data type is for
       consistency with the respective grab request and the
       status code of the XIGrabModifiers struct is ignored.

modifiers_inout
       Specifies the set of latched and base modifiers or
       XIAnyModifier to grab. Returns the modifiers that could
       not be grabbed and their error code.

grab_window
       Specifies the grab window.

owner_events
       Specifies a Boolean value that indicates whether the are
       to be reported as usual or reported with respect to the
       grab window.

mask
       Specifies the event mask.

grab_mode
       Specifies further processing of events from this device.
       You can pass XIGrabModeSync or XIGrabModeAsync.

paired_device_mode
       Specifies further processing of events from the paired
       master device. You can pass XIGrabModeSync or
       XIGrabModeAsync. If deviceid specifies a floating slave
       device, this parameter is ignored.

DESCRIPTION

    XIGrabButton, XIGrabKeycode and XIGrabTouchBegin establish a passive
    grab. The modifier device for a button grab is the paired master device
    if deviceid specifies a master pointer. Otherwise, the modifier
    device is the device specified with deviceid. In the future,
    the device is actively grabbed (as for XIGrabDevice, the
    last-grab time is set to the time at which the button or keycode
    was pressed and the XI_ButtonPress or XI_KeyPress event is
    reported if all of the following conditions are true:
      * The device is not grabbed, and the specified button or
        keycode is logically pressed or a touch event occurs when the
        specified modifier keys are logically down on the modifier device
        and no other buttons or modifier keys are logically down.
      * Either the grab window is an ancestor of (or is) the focus
        window, OR the grab window is a descendent of the focus
        window and contains the device.
      * A passive grab on the same button/modifier combination does
        not exist on any ancestor of grab_window.

    The interpretation of the remaining arguments is as for
    XIGrabDevice. The active grab is terminated automatically when
    the logical state of the device has all buttons or keys
    released (independent of the logical state of the modifier
    keys).

    If the device is an attached slave device, the device is
    automatically detached from the master device when the grab
    activates and reattached to the same master device when the
    grab deactivates. If the master device is removed while the
    device is floating as a result of a grab, the device remains
    floating once the grab deactivates.

    Note that the logical state of a device (as seen by client
    applications) may lag the physical state if device event
    processing is frozen.

    This request overrides all previous grabs by the same client on
    the same button/modifier or keycode/modifier combinations on the
    same window. A modifiers of XIAnyModifier is equivalent to
    issuing the grab request for all possible modifier combinations
    (including the combination of no modifiers). It is not required
    that all modifiers specified have currently assigned KeyCodes.
    A button of XIAnyButton is equivalent to issuing the request
    for all possible buttons. Otherwise, it is not required that
    the specified button currently be assigned to a physical
    button.

    If some other client has already issued a XIGrabButton or
    XIGrabKeycode with the same button/modifier or keycode/modifier
    combination on the same window, a BadAccess error results. When
    using XIAnyModifier or XIAnyButton , the request fails
    completely, and a XIBadAccess error results (no grabs are
    established) if there is a conflicting grab for any
    combination. XIGrabButton and XIGrabKeycode have no effect on an
    active grab.

    On success, XIGrabButton, XIGrabKeycode and XIGrabTouchBegin return 0;
    If one or more modifier combinations could not be grabbed,
    XIGrabButton, XIGrabKeycode and XIGrabTouchBegin return the number of
    failed combinations and modifiers_inout contains the failed combinations
    and their respective error codes.

    XIGrabButton, XIGrabKeycode and XIGrabTouchBegin can generate BadClass,
    BadDevice, BadMatch, BadValue, and BadWindow errors.

    XIUngrabButton, XIUngrabKeycode and XIUngrabTouchBegin release the
    passive grab for a button/modifier, keycode/modifier or touch/modifier
    combination on the specified window if it was grabbed by this client. A
    modifier of XIAnyModifier is equivalent to issuing the ungrab request
    for all possible modifier combinations, including the
    combination of no modifiers. A button of XIAnyButton is
    equivalent to issuing the request for all possible buttons.
    XIUngrabButton and XIUngrabKeycode have no effect on an active
    grab.

    XIUngrabButton, XIUngrabKeycode and XIUngrabTouchBegin can generate
    BadDevice, BadMatch, BadValue and BadWindow errors.

RETURN VALUE

    XIGrabButton, XIGrabKeycode and XIGrabTouchBegin return the number of
    modifier combination that could not establish a passive grab. The
    modifiers are returned in modifiers_inout, along with the respective
    error for this modifier combination. If XIGrabButton, XIGrabKeycode
    or XIGrabTouchBegin return zero, passive grabs with all requested
    modifier combinations were established successfully.

DIAGNOSTICS

    BadDevice
           An invalid deviceid was specified.

    BadMatch
           This error may occur if XIGrabButton specified a device
           that has no buttons, or XIGrabKeycode specified a device
           that has no keys, or XIGrabTouchBegin specified a device
           that is not touch-capable.

    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.

    BadWindow
           A value for a Window argument does not name a defined
           Window.

BUGS

    The protocol headers for XI 2.0 did not provide
    XIGrabModeAsync or XIGrabModeSync. Use GrabModeSync and
    GrabModeAsync instead, respectively.

SEE ALSO

    XIAllowEvents(3)