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xcb_grab_pointer(3)		  XCB Requests		     xcb_grab_pointer(3)

NAME
     xcb_grab_pointer - Grab the pointer

SYNOPSIS
     #include <xcb/xproto.h>

   Request function
     xcb_grab_pointer_cookie_t		xcb_grab_pointer(xcb_connection_t *conn,
	    uint8_t owner_events, xcb_window_t grab_window, uint16_t event_mask,
	    uint8_t pointer_mode,    uint8_t keyboard_mode,    xcb_window_t con-
	    fine_to, xcb_cursor_t cursor, xcb_timestamp_t time);

   Reply datastructure
     typedef struct xcb_grab_pointer_reply_t {
	 uint8_t  response_type;
	 uint8_t  status;
	 uint16_t sequence;
	 uint32_t length;
     } xcb_grab_pointer_reply_t;

   Reply function
     xcb_grab_pointer_reply_t	 *xcb_grab_pointer_reply(xcb_connection_t *conn,
	    xcb_grab_pointer_cookie_t cookie, xcb_generic_error_t **e);

REQUEST ARGUMENTS
     conn      The XCB connection to X11.

     owner_events
	       If 1, the grab_window will still get the pointer  events.  If  0,
	       events are not reported to the grab_window.

     grab_window
	       Specifies the window on which the pointer should be grabbed.

     event_maskSpecifies which pointer events are reported to the client.

	       TODO: which values?

     pointer_mode
	       One of the following values:

	       XCB_GRAB_MODE_SYNC
			 The state of the keyboard appears to freeze: No further
			 keyboard  events  are generated by the server until the
			 grabbing client issues a releasing AllowEvents  request
			 or until the keyboard grab is released.

	       XCB_GRAB_MODE_ASYNC
			 Keyboard event processing continues normally.

     keyboard_mode
	       One of the following values:

	       XCB_GRAB_MODE_SYNC
			 The state of the keyboard appears to freeze: No further
			 keyboard  events  are generated by the server until the
			 grabbing client issues a releasing AllowEvents  request
			 or until the keyboard grab is released.

	       XCB_GRAB_MODE_ASYNC
			 Keyboard event processing continues normally.

     confine_toSpecifies the window to confine the pointer in (the user will not
	       be able to move the pointer out of that window).

	       The special value XCB_NONE means don't confine the pointer.

     cursor    Specifies  the cursor that should be displayed or XCB_NONE to not
	       change the cursor.

     time      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 applica-
	       tion then will get  an  indication  that  the  other  application
	       grabbed the pointer before its request was processed.

	       The special value XCB_CURRENT_TIME will be replaced with the cur-
	       rent server time.

REPLY FIELDS
     response_type
	       The type of this reply, in this case XCB_GRAB_POINTER. This field
	       is  also  present  in  the xcb_generic_reply_t and can be used to
	       tell replies apart from each other.

     sequence  The sequence number of the last	request  processed  by	the  X11
	       server.

     length    The length of the reply, in words (a word is 4 bytes).

     status    One of the following values:

	       XCB_GRAB_STATUS_SUCCESS
			 TODO: NOT YET DOCUMENTED.

	       XCB_GRAB_STATUS_ALREADY_GRABBED
			 TODO: NOT YET DOCUMENTED.

	       XCB_GRAB_STATUS_INVALID_TIME
			 TODO: NOT YET DOCUMENTED.

	       XCB_GRAB_STATUS_NOT_VIEWABLE
			 TODO: NOT YET DOCUMENTED.

	       XCB_GRAB_STATUS_FROZEN
			 TODO: NOT YET DOCUMENTED.
	       TODO: NOT YET DOCUMENTED.

DESCRIPTION
     Actively  grabs control of the pointer. Further pointer events are reported
     only to the grabbing client. Overrides any  active  pointer  grab	by  this
     client.

RETURN VALUE
     Returns  an xcb_grab_pointer_cookie_t. Errors have to be handled when call-
     ing the reply function xcb_grab_pointer_reply.

     If  you  want  to	handle	errors	in   the   event   loop   instead,   use
     xcb_grab_pointer_unchecked. See xcb-requests(3) for details.

ERRORS
     xcb_value_error_t
	       TODO: reasons?

     xcb_window_error_t
	       The specified window does not exist.

EXAMPLE
     /*
      * Grabs the pointer actively
      *
      */
     void my_example(xcb_connection_t *conn, xcb_screen_t *screen, xcb_cursor_t cursor) {
	 xcb_grab_pointer_cookie_t cookie;
	 xcb_grab_pointer_reply_t *reply;

	 cookie = xcb_grab_pointer(
	     conn,
	     false,		  /* get all pointer events specified by the following mask */
	     screen->root,	  /* grab the root window */
	     XCB_NONE,		  /* which events to let through */
	     XCB_GRAB_MODE_ASYNC, /* pointer events should continue as normal */
	     XCB_GRAB_MODE_ASYNC, /* keyboard mode */
	     XCB_NONE,		  /* confine_to = in which window should the cursor stay */
	     cursor,		  /* we change the cursor to whatever the user wanted */
	     XCB_CURRENT_TIME
	 );

	 if ((reply = xcb_grab_pointer_reply(conn, cookie, NULL))) {
	     if (reply->status == XCB_GRAB_STATUS_SUCCESS)
		 printf("successfully grabbed the pointer\n");
	     free(reply);
	 }
     }

SEE ALSO
     xcb-requests(3), xcb-examples(3), xcb_grab_keyboard(3)

AUTHOR
     Generated	from  xproto.xml.  Contact xcb@lists.freedesktop.org for correc-
     tions and improvements.

X Version 11			  libxcb 1.17.0 	     xcb_grab_pointer(3)

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