Index for Section 3X11

Alphabetical listing for X

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XGrabPointer(3X11)
X11R6
NAME
  XGrabPointer, XUngrabPointer, XChangeActivePointerGrab - grab the pointer

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

  XUngrabPointer(display, time)
	  Display *display;
	  Time time;

  XChangeActivePointerGrab(display, event_mask, cursor, time)
	  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 inclusive 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 GrabModeAsync.

  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 GrabModeAsync.

  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 overrides 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 XAllowEvents 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 applications, 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 reconfigured, 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 applications, 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 completely 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 specified 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
  parameters 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

Index for Section 3X11

Alphabetical listing for X

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