xcb_grab_key(3) XCB Requests xcb_grab_key(3)
NAME
xcb_grab_key - Grab keyboard key(s)
SYNOPSIS
#include <xcb/xproto.h>
Request function
xcb_void_cookie_t xcb_grab_key(xcb_connection_t *conn,
uint8_t owner_events, xcb_window_t grab_window,
uint16_t modifiers, xcb_keycode_t key, uint8_t pointer_mode,
uint8_t keyboard_mode);
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.
modifiers The modifiers to grab.
Using the special value XCB_MOD_MASK_ANY means grab the
pointer with all possible modifier combinations.
key The keycode of the key to grab.
The special value XCB_GRAB_ANY means grab any key.
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 Allow-
Events request or until the keyboard grab is re-
leased.
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 Allow-
Events request or until the keyboard grab is re-
leased.
XCB_GRAB_MODE_ASYNC
Keyboard event processing continues normally.
DESCRIPTION
Establishes a passive grab on the keyboard. In the future, the keyboard
is actively grabbed (as for GrabKeyboard), the last-keyboard-grab time
is set to the time at which the key was pressed (as transmitted in the
KeyPress event), and the KeyPress event is reported if all of the fol-
lowing conditions are true:
The keyboard is not grabbed and the specified key (which can itself be
a modifier key) is logically pressed when the specified modifier keys
are logically down, and no other modifier keys are logically down.
Either the grab_window is an ancestor of (or is) the focus window, or
the grab_window is a descendant of the focus window and contains the
pointer.
A passive grab on the same key combination does not exist on any ances-
tor of grab_window.
The interpretation of the remaining arguments is as for XGrabKeyboard.
The active grab is terminated automatically when the logical state of
the keyboard has the specified key released (independent of the logical
state of the modifier keys), at which point a KeyRelease event is re-
ported to the grabbing window.
Note that the logical state of a device (as seen by client applica-
tions) may lag the physical state if device event processing is frozen.
A modifiers argument of AnyModifier is equivalent to issuing the re-
quest for all possible modifier combinations (including the combination
of no modifiers). It is not required that all modifiers specified have
currently assigned KeyCodes. A keycode argument of AnyKey is equiva-
lent to issuing the request for all possible KeyCodes. Otherwise, the
specified keycode must be in the range specified by min_keycode and
max_keycode in the connection setup, or a BadValue error results.
If some other client has issued a XGrabKey with the same key combina-
tion on the same window, a BadAccess error results. When using AnyMod-
ifier or AnyKey, the request fails completely, and a BadAccess error
results (no grabs are established) if there is a conflicting grab for
any combination.
RETURN VALUE
Returns an xcb_void_cookie_t. Errors (if any) have to be handled in the
event loop.
If you want to handle errors directly with xcb_request_check instead,
use xcb_grab_key_checked. See xcb-requests(3) for details.
ERRORS
xcb_access_error_t
Another client has already issued a GrabKey with the same
button/key combination on the same window.
xcb_value_error_t
TODO: reasons?
xcb_window_error_t
The specified window does not exist.
SEE ALSO
xcb-requests(3), xcb_grab_keyboard(3)
AUTHOR
Generated from xproto.xml. Contact xcb@lists.freedesktop.org for cor-
rections and improvements.
X Version 11 libxcb 1.14 xcb_grab_key(3)
xorg-libxcb 1.14 - Generated Sun Mar 22 10:30:13 CDT 2020