XAnyEvent(3X11) X Version 11 (Release 4) XAnyEvent(3X11)
NAME
XAnyEvent, XEvent - generic X event structures
STRUCTURES
All the event structures declared in <X11/Xlib.h> have the
following common members:
typedef struct {
int type;
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;
} XAnyEvent;
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 XEvent structure is a union of the individual structures
declared for each event type:
typedef union _XEvent {
int type; /* must not be changed */
XAnyEvent xany;
XKeyEvent xkey;
XButtonEvent xbutton;
XMotionEvent xmotion;
XCrossingEvent xcrossing;
XFocusChangeEvent xfocus;
XExposeEvent xexpose;
XGraphicsExposeEvent xgraphicsexpose;
XNoExposeEvent xnoexpose;
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XAnyEvent(3X11) X Version 11 (Release 4) XAnyEvent(3X11)
XVisibilityEvent xvisibility;
XCreateWindowEvent xcreatewindow;
XDestroyWindowEvent xdestroywindow;
XUnmapEvent xunmap;
XMapEvent xmap;
XMapRequestEvent xmaprequest;
XReparentEvent xreparent;
XConfigureEvent xconfigure;
XGravityEvent xgravity;
XResizeRequestEvent xresizerequest;
XConfigureRequestEvent xconfigurerequest;
XCirculateEvent xcirculate;
XCirculateRequestEvent xcirculaterequest;
XPropertyEvent xproperty;
XSelectionClearEvent xselectionclear;
XSelectionRequestEvent xselectionrequest;
XSelectionEvent xselection;
XColormapEvent xcolormap;
XClientMessageEvent xclient;
XMappingEvent xmapping;
XErrorEvent xerror;
XKeymapEvent xkeymap;
long pad[24];
} XEvent;
An XEvent structure's first entry always is the type member,
which is set to the event type. The second member always is
the serial number of the protocol request that generated the
event. The third member always is send_event, which is a
Bool that indicates if the event was sent by a different
client. The fourth member always is a display, which is the
display that the event was read from. Except for keymap
events, the fifth member always is a window, which has been
carefully selected to be useful to toolkit dispatchers. To
avoid breaking toolkits, the order of these first five
entries is not to change. Most events also contain a time
member, which is the time at which an event occurred. In
addition, a pointer to the generic event must be cast before
it is used to access any other information in the structure.
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SEE ALSO
XButtonEvent(3X11), XCreateWindowEvent(3X11),
XCirculateEvent(3X11), XCirculateRequestEvent(3X11),
XColormapEvent(3X11), XConfigureEvent(3X11),
XConfigureRequestEvent(3X11), XCrossingEvent(3X11),
XDestroyWindowEvent(3X11), XErrorEvent(3X11),
XExposeEvent(3X11), XFocusChangeEvent(3X11),
XGraphicsExposeEvent(3X11), XGravityEvent(3X11),
XKeymapEvent(3X11), XMapEvent(3X11), XMapRequestEvent(3X11),
XPropertyEvent(3X11), XReparentEvent(3X11),
XResizeRequestEvent(3X11), XSelectionClearEvent(3X11),
XSelectionEvent(3X11), XSelectionRequestEvent(3X11),
XUnmapEvent(3X11), XVisibilityEvent(3X11)
Xlib - C Language X Interface
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