NAME

       XCrossingEvent - EnterNotify and LeaveNotify event structure

STRUCTURES

       The structure for EnterNotify and LeaveNotify events contains:

       typedef struct {
               int type;       /* EnterNotify or LeaveNotify */
               unsigned long serial;   /* # of last request processed by server */
               Bool send_event;        /* true if this came from a SendEvent request */
               Display *display;       /* Display the event was read from */
               Window window;  /* “event” window reported relative to */
               Window root;    /* root window that the event occurred on */
               Window subwindow;       /* child window */
               Time time;      /* milliseconds */
               int x, y;       /* pointer x, y coordinates in event window */
               int x_root, y_root;     /* coordinates relative to root */
               int mode;       /* NotifyNormal, NotifyGrab, NotifyUngrab */
               int detail;
                       /*
                       * NotifyAncestor, NotifyVirtual, NotifyInferior,
                       * NotifyNonlinear,NotifyNonlinearVirtual
                       */
               Bool same_screen;       /* same screen flag */
               Bool focus;     /* boolean focus */
               unsigned int state;     /* key or button mask */
       } XCrossingEvent;
       typedef XCrossingEvent XEnterWindowEvent;
       typedef XCrossingEvent XLeaveWindowEvent;

       When you receive these events, the structure members are set as follows.

       The  type  member is set to the event type constant name that uniquely identifies it.  For
       example, when the X server reports a GraphicsExpose event  to  a  client  application,  it
       sends  an  XGraphicsExposeEvent structure with the type member set to GraphicsExpose.  The
       display member is set to a pointer to the display the event was read on.   The  send_event
       member  is  set  to  True if the event came from a SendEvent protocol request.  The serial
       member is set from the serial number reported in the protocol but expanded from the 16-bit
       least-significant  bits  to  a  full 32-bit value.  The window member is set to the window
       that is most useful to toolkit dispatchers.

       The window member is set to the window on which the EnterNotify or LeaveNotify  event  was
       generated and is referred to as the event window.  This is the window used by the X server
       to report the event, and is relative to the root window on which the event occurred.   The
       root member is set to the root window of the screen on which the event occurred.

       For  a  LeaveNotify event, if a child of the event window contains the initial position of
       the pointer, the subwindow component is set to that child.  Otherwise, the X  server  sets
       the  subwindow  member  to None.  For an EnterNotify event, if a child of the event window
       contains the final pointer position, the subwindow component is set to that child or None.

       The time member is set to the time when the  event  was  generated  and  is  expressed  in
       milliseconds.   The  x and y members are set to the coordinates of the pointer position in
       the event window.  This position is always the pointer's final position, not  its  initial
       position.   If  the event window is on the same screen as the root window, x and y are the
       pointer coordinates relative to the event window's origin.  Otherwise, x and y are set  to
       zero.   The x_root and y_root members are set to the pointer's coordinates relative to the
       root window's origin at the time of the event.

       The same_screen member is set to indicate whether the event window is on the  same  screen
       as  the  root window and can be either True or False.  If True, the event and root windows
       are on the same screen.  If False, the event and root windows are not on the same screen.

       The focus member is set to indicate whether the event window is the  focus  window  or  an
       inferior  of  the focus window.  The X server can set this member to either True or False.
       If True, the event window is the focus window or an inferior  of  the  focus  window.   If
       False, the event window is not the focus window or an inferior of the focus window.

       The  state  member  is  set to indicate the state of the pointer buttons and modifier keys
       just prior to the event.  The X server can set this member to the bitwise inclusive OR  of
       one  or  more  of the button or modifier key masks: Button1Mask, Button2Mask, Button3Mask,
       Button4Mask, Button5Mask, ShiftMask, LockMask, ControlMask, Mod1Mask, Mod2Mask,  Mod3Mask,
       Mod4Mask, Mod5Mask.

       The  mode  member  is  set to indicate whether the events are normal events, pseudo-motion
       events when a grab activates, or pseudo-motion events when  a  grab  deactivates.   The  X
       server can set this member to NotifyNormal, NotifyGrab, or NotifyUngrab.

       The  detail  member  is  set  to  indicate  the  notify  detail and can be NotifyAncestor,
       NotifyVirtual, NotifyInferior, NotifyNonlinear, or NotifyNonlinearVirtual.

SEE ALSO

       XAnyEvent(3),      XButtonEvent(3),       XCreateWindowEvent(3),       XCirculateEvent(3),
       XCirculateRequestEvent(3),              XColormapEvent(3),             XConfigureEvent(3),
       XConfigureRequestEvent(3),   XDestroyWindowEvent(3),   XErrorEvent(3),    XExposeEvent(3),
       XFocusChangeEvent(3),    XGraphicsExposeEvent(3),    XGravityEvent(3),    XKeymapEvent(3),
       XMapEvent(3),       XMapRequestEvent(3),       XPropertyEvent(3),       XReparentEvent(3),
       XResizeRequestEvent(3),            XSelectionClearEvent(3),            XSelectionEvent(3),
       XSelectionRequestEvent(3), XUnmapEvent(3), XVisibilityEvent(3)
       Xlib - C Language X Interface