NAME
XQueryPointer − get the current pointer location.
Synopsis
Bool XQueryPointer(display, w, root_return, child_return, root_x_return, route_y_return,
win_x_return, win_y_return, mask_return)
Display *display;
Window w;
Window *root_return, *child_return;
int *root_x_return, *route_y_return;
int *win_x_return, *win_y_return;
unsigned int *mask_return;
Arguments
displaySpecifies a connection to an X server; returned from XOpenDisplay().
wSpecifies a window which indicates which screen the pointer position is returned for, and child_return will be a child of this window if pointer is inside a child.
root_return
Returns the root window ID the pointer is currently on.
child_return
Returns the ID of the child of w the pointer is located in, or zero if it not in a child.
root_x_return
route_y_return
Return the x and y coordinates of the pointer relative to the root’s origin.
win_x_return
win_y_return
Return the x and y coordinates of the pointer relative to the origin of window w.
mask_return
Returns the current state of the modifier keys and pointer buttons. This is a mask composed of the OR of any number of the following symbols: ShiftMask, LockMask, ControlMask, Mod1Mask, Mod2Mask, Mod3Mask, Mod4Mask, Mod5Mask, Button1Mask, Button2Mask, Button3Mask, Button4Mask, Button5Mask.
Description
XQueryPointer() gets the pointer coordinates relative to a window and relative to the root window, the root_return window ID and the child_return window ID (if any) the pointer is currently in, and the current state of modifier keys and buttons. If XQueryPointer() returns False, then the pointer is not on the same screen as w, child_return is None, and win_x_return and win_y_return are zero. However, root_return, root_x_return, and route_y_return are still valid. If XQueryPointer() returns True, then the pointer is on the same screen as the window w, and all return values are valid. The logical state of the pointer buttons and modifier keys can lag behind their physical state if device event processing is frozen due to a grab.
Errors
BadWindow
See Also
XChangeActivePointerGrab(), XChangePointerControl(), XGetPointerControl(), XGetPointerMapping(), XGrabPointer(), XSetPointerMapping(), XUngrabPointer(), XWarpPointer().
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