1xcb_grab_pointer(3) XCB Requests xcb_grab_pointer(3)
2
6 xcb_grab_pointer - Grab the pointer
7
9 #include <xcb/xproto.h>
10 Request function
12 xcb_grab_pointer_cookie_t xcb_grab_pointer(xcb_connection_t *conn,
13 uint8_t owner_events, xcb_window_t grab_window,
14 uint16_t event_mask, uint8_t pointer_mode,
15 uint8_t keyboard_mode, xcb_window_t confine_to,
16 xcb_cursor_t cursor, xcb_timestamp_t time);
17 Reply datastructure
19 typedef struct xcb_grab_pointer_reply_t {
20 uint8_t response_type;
21 uint8_t status;
22 uint16_t sequence;
23 uint32_t length;
24 } xcb_grab_pointer_reply_t;
25 Reply function
27 xcb_grab_pointer_reply_t
28 *xcb_grab_pointer_reply(xcb_connection_t *conn,
29 xcb_grab_pointer_cookie_t cookie, xcb_generic_error_t **e);
30
32 conn The XCB connection to X11.
33 owner_events
35 If 1, the grab_window will still get the pointer events. If
36 0, events are not reported to the grab_window.
37 grab_window
39 Specifies the window on which the pointer should be grabbed.
40 event_mask
42 Specifies which pointer events are reported to the client.
43 TODO: which values?
45 pointer_mode
47 One of the following values:
48 XCB_GRAB_MODE_SYNC
50 The state of the keyboard appears to freeze: No
51 further keyboard events are generated by the server
52 until the grabbing client issues a releasing Allow‐
53 Events request or until the keyboard grab is re‐
54 leased.
55 XCB_GRAB_MODE_ASYNC
57 Keyboard event processing continues normally.
58 keyboard_mode
62 One of the following values:
63 XCB_GRAB_MODE_SYNC
65 The state of the keyboard appears to freeze: No
66 further keyboard events are generated by the server
67 until the grabbing client issues a releasing Allow‐
68 Events request or until the keyboard grab is re‐
69 leased.
70 XCB_GRAB_MODE_ASYNC
72 Keyboard event processing continues normally.
73 confine_to
77 Specifies the window to confine the pointer in (the user will
78 not be able to move the pointer out of that window).
79 The special value XCB_NONE means don't confine the pointer.
81 cursor Specifies the cursor that should be displayed or XCB_NONE to
83 not change the cursor.
84 time The time argument allows you to avoid certain circumstances
86 that come up if applications take a long time to respond or
87 if there are long network delays. Consider a situation where
88 you have two applications, both of which normally grab the
89 pointer when clicked on. If both applications specify the
90 timestamp from the event, the second application may wake up
91 faster and successfully grab the pointer before the first ap‐
92 plication. The first application then will get an indication
93 that the other application grabbed the pointer before its re‐
94 quest was processed.
95 The special value XCB_CURRENT_TIME will be replaced with the
97 current server time.
98
100 response_type
101 The type of this reply, in this case XCB_GRAB_POINTER. This
102 field is also present in the xcb_generic_reply_t and can be
103 used to tell replies apart from each other.
104 sequence The sequence number of the last request processed by the X11
106 server.
107 length The length of the reply, in words (a word is 4 bytes).
109 status One of the following values:
111 XCB_GRAB_STATUS_SUCCESS
113 TODO: NOT YET DOCUMENTED.
114 XCB_GRAB_STATUS_ALREADY_GRABBED
116 TODO: NOT YET DOCUMENTED.
117 XCB_GRAB_STATUS_INVALID_TIME
119 TODO: NOT YET DOCUMENTED.
120 XCB_GRAB_STATUS_NOT_VIEWABLE
122 TODO: NOT YET DOCUMENTED.
123 XCB_GRAB_STATUS_FROZEN
125 TODO: NOT YET DOCUMENTED.
126 TODO: NOT YET DOCUMENTED.
127
129 Actively grabs control of the pointer. Further pointer events are re‐
130 ported only to the grabbing client. Overrides any active pointer grab
131 by this client.
132
134 Returns an xcb_grab_pointer_cookie_t. Errors have to be handled when
135 calling the reply function xcb_grab_pointer_reply.
136 If you want to handle errors in the event loop instead, use
138 xcb_grab_pointer_unchecked. See xcb-requests(3) for details.
139
141 xcb_value_error_t
142 TODO: reasons?
143 xcb_window_error_t
145 The specified window does not exist.
146
148 /*
149 * Grabs the pointer actively
150 *
151 */
152 void my_example(xcb_connection_t *conn, xcb_screen_t *screen, xcb_cursor_t cursor) {
153 xcb_grab_pointer_cookie_t cookie;
154 xcb_grab_pointer_reply_t *reply;
155 cookie = xcb_grab_pointer(
157 conn,
158 false, /* get all pointer events specified by the following mask */
159 screen->root, /* grab the root window */
160 XCB_NONE, /* which events to let through */
161 XCB_GRAB_MODE_ASYNC, /* pointer events should continue as normal */
162 XCB_GRAB_MODE_ASYNC, /* keyboard mode */
163 XCB_NONE, /* confine_to = in which window should the cursor stay */
164 cursor, /* we change the cursor to whatever the user wanted */
165 XCB_CURRENT_TIME
166 );
167 if ((reply = xcb_grab_pointer_reply(conn, cookie, NULL))) {
169 if (reply->status == XCB_GRAB_STATUS_SUCCESS)
170 printf("successfully grabbed the pointer\n");
171 free(preply);
172 }
173 }
174
176 xcb-requests(3), xcb-examples(3), xcb_grab_keyboard(3)
177
179 Generated from xproto.xml. Contact xcb@lists.freedesktop.org for cor‐
180 rections and improvements.
181X Version 11 libxcb 1.12 xcb_grab_pointer(3)