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XGrabPointer(3)                                XLIB FUNCTIONS                                XGrabPointer(3)



NAME
       XGrabPointer, XUngrabPointer, XChangeActivePointerGrab - grab the pointer

SYNTAX
       int XGrabPointer(Display *display, Window grab_window, Bool owner_events, unsigned int event_mask,
              int pointer_mode, int keyboard_mode, Window confine_to, Cursor cursor, Time time);

       int XUngrabPointer(Display *display, Time time);

       int XChangeActivePointerGrab(Display *display, unsigned int event_mask, Cursor cursor, Time time);

ARGUMENTS
       confine_to
                 Specifies the window to confine the pointer in or None.

       cursor    Specifies the cursor that is to be displayed during the grab or None.

       display   Specifies the connection to the X server.

       event_mask
                 Specifies which pointer events are reported to the client.  The mask is the bitwise inclu-sive inclusive
                 sive OR of the valid pointer event mask bits.

       grab_window
                 Specifies the grab window.

       keyboard_mode
                 Specifies further processing of keyboard events.  You can pass GrabModeSync or GrabMod-eAsync. GrabModeAsync.
                 eAsync.

       owner_events
                 Specifies a Boolean value that indicates whether the pointer events are to be reported as
                 usual or reported with respect to the grab window if selected by the event mask.

       pointer_mode
                 Specifies further processing of pointer events.  You can pass GrabModeSync or GrabMod-eAsync. GrabModeAsync.
                 eAsync.

       time      Specifies the time.  You can pass either a timestamp or CurrentTime.

DESCRIPTION
       The XGrabPointer function actively grabs control of the pointer and returns GrabSuccess if the grab
       was successful.  Further pointer events are reported only to the grabbing client.  XGrabPointer over-rides overrides
       rides any active pointer grab by this client.  If owner_events is False, all generated pointer events
       are reported with respect to grab_window and are reported only if selected by event_mask.  If
       owner_events is True and if a generated pointer event would normally be reported to this client, it
       is reported as usual.  Otherwise, the event is reported with respect to the grab_window and is
       reported only if selected by event_mask.  For either value of owner_events, unreported events are
       discarded.

       If the pointer_mode is GrabModeAsync, pointer event processing continues as usual.  If the pointer is
       currently frozen by this client, the processing of events for the pointer is resumed.  If the
       pointer_mode is GrabModeSync, the state of the pointer, as seen by client applications, appears to
       freeze, and the X server generates no further pointer events until the grabbing client calls XAllow-Events XAllowEvents
       Events or until the pointer grab is released.  Actual pointer changes are not lost while the pointer
       is frozen; they are simply queued in the server for later processing.

       If the keyboard_mode is GrabModeAsync, keyboard event processing is unaffected by activation of the
       grab.  If the keyboard_mode is GrabModeSync, the state of the keyboard, as seen by client applica-tions, applications,
       tions, appears to freeze, and the X server generates no further keyboard events until the grabbing
       client calls XAllowEvents or until the pointer grab is released.  Actual keyboard changes are not
       lost while the pointer is frozen; they are simply queued in the server for later processing.

       If a cursor is specified, it is displayed regardless of what window the pointer is in.  If None is
       specified, the normal cursor for that window is displayed when the pointer is in grab_window or one
       of its subwindows; otherwise, the cursor for grab_window is displayed.

       If a confine_to window is specified, the pointer is restricted to stay contained in that window.  The
       confine_to window need have no relationship to the grab_window.  If the pointer is not initially in
       the confine_to window, it is warped automatically to the closest edge just before the grab activates
       and enter/leave events are generated as usual.  If the confine_to window is subsequently reconfig-ured, reconfigured,
       ured, the pointer is warped automatically, as necessary, to keep it contained in the window.

       The time argument allows you to avoid certain circumstances that come up if applications take a long
       time to respond or if there are long network delays.  Consider a situation where you have two appli-cations, applications,
       cations, both of which normally grab the pointer when clicked on.  If both applications specify the
       timestamp from the event, the second application may wake up faster and successfully grab the pointer
       before the first application.  The first application then will get an indication that the other
       application grabbed the pointer before its request was processed.

       XGrabPointer generates EnterNotify and LeaveNotify events.

       Either if grab_window or confine_to window is not viewable or if the confine_to window lies com-pletely completely
       pletely outside the boundaries of the root window, XGrabPointer fails and returns GrabNotViewable.
       If the pointer is actively grabbed by some other client, it fails and returns AlreadyGrabbed.  If the
       pointer is frozen by an active grab of another client, it fails and returns GrabFrozen.  If the spec-ified specified
       ified time is earlier than the last-pointer-grab time or later than the current X server time, it
       fails and returns GrabInvalidTime.  Otherwise, the last-pointer-grab time is set to the specified
       time (CurrentTime is replaced by the current X server time).

       XGrabPointer can generate BadCursor, BadValue, and BadWindow errors.

       The XUngrabPointer function releases the pointer and any queued events if this client has actively
       grabbed the pointer from XGrabPointer, XGrabButton, or from a normal button press.  XUngrabPointer
       does not release the pointer if the specified time is earlier than the last-pointer-grab time or is
       later than the current X server time.  It also generates EnterNotify and LeaveNotify events.  The X
       server performs an UngrabPointer request automatically if the event window or confine_to window for
       an active pointer grab becomes not viewable or if window reconfiguration causes the confine_to window
       to lie completely outside the boundaries of the root window.

       The XChangeActivePointerGrab function changes the specified dynamic parameters if the pointer is
       actively grabbed by the client and if the specified time is no earlier than the last-pointer-grab
       time and no later than the current X server time.  This function has no effect on the passive parame-ters parameters
       ters of a XGrabButton.  The interpretation of event_mask and cursor is the same as described in
       XGrabPointer.

       XChangeActivePointerGrab can generate a BadCursor and BadValue error.

DIAGNOSTICS
       BadCursor A value for a Cursor argument does not name a defined Cursor.

       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.

SEE ALSO
       XAllowEvents(3X11), XGrabButton(3X11), XGrabKey(3X11), XGrabKeyboard(3X11)
       Xlib - C Language X Interface



X Version 11                                    libX11 1.2.1                                 XGrabPointer(3)