NAME
XNextEvent, XPeekEvent, XWindowEvent, XCheckWindowEvent, XMaskEvent,
XCheckMaskEvent, XCheckTypedEvent, XCheckTypedWindowEvent - select
events by type
SYNTAX
int XNextEvent(Display *display, XEvent *event_return);
int XPeekEvent(Display *display, XEvent *event_return);
int XWindowEvent(Display *display, Window w, long event_mask, XEvent
*event_return);
Bool XCheckWindowEvent(Display *display, Window w, long event_mask,
XEvent *event_return);
int XMaskEvent(Display *display, long event_mask, XEvent
*event_return);
Bool XCheckMaskEvent(Display *display, long event_mask, XEvent
*event_return);
Bool XCheckTypedEvent(Display *display, int event_type, XEvent
*event_return);
Bool XCheckTypedWindowEvent(Display *display, Window w, int event_type,
XEvent *event_return);
ARGUMENTS
display Specifies the connection to the X server.
event_mask
Specifies the event mask.
event_return
Returns the matched event’s associated structure.
event_return
Returns the next event in the queue.
event_return
Returns a copy of the matched event’s associated structure.
event_type
Specifies the event type to be compared.
w Specifies the window whose event uou are interested in.
DESCRIPTION
The XNextEvent function copies the first event from the event queue
into the specified XEvent structure and then removes it from the queue.
If the event queue is empty, XNextEvent flushes the output buffer and
blocks until an event is received.
The XPeekEvent function returns the first event from the event queue,
but it does not remove the event from the queue. If the queue is
empty, XPeekEvent flushes the output buffer and blocks until an event
is received. It then copies the event into the client-supplied XEvent
structure without removing it from the event queue.
The XWindowEvent function searches the event queue for an event that
matches both the specified window and event mask. When it finds a
match, XWindowEvent removes that event from the queue and copies it
into the specified XEvent structure. The other events stored in the
queue are not discarded. If a matching event is not in the queue,
XWindowEvent flushes the output buffer and blocks until one is
received.
The XCheckWindowEvent function searches the event queue and then the
events available on the server connection for the first event that
matches the specified window and event mask. If it finds a match,
XCheckWindowEvent removes that event, copies it into the specified
XEvent structure, and returns True. The other events stored in the
queue are not discarded. If the event you requested is not available,
XCheckWindowEvent returns False, and the output buffer will have been
flushed.
The XMaskEvent function searches the event queue for the events
associated with the specified mask. When it finds a match, XMaskEvent
removes that event and copies it into the specified XEvent structure.
The other events stored in the queue are not discarded. If the event
you requested is not in the queue, XMaskEvent flushes the output buffer
and blocks until one is received.
The XCheckMaskEvent function searches the event queue and then any
events available on the server connection for the first event that
matches the specified mask. If it finds a match, XCheckMaskEvent
removes that event, copies it into the specified XEvent structure, and
returns True. The other events stored in the queue are not discarded.
If the event you requested is not available, XCheckMaskEvent returns
False, and the output buffer will have been flushed.
The XCheckTypedEvent function searches the event queue and then any
events available on the server connection for the first event that
matches the specified type. If it finds a match, XCheckTypedEvent
removes that event, copies it into the specified XEvent structure, and
returns True. The other events in the queue are not discarded. If the
event is not available, XCheckTypedEvent returns False, and the output
buffer will have been flushed.
The XCheckTypedWindowEvent function searches the event queue and then
any events available on the server connection for the first event that
matches the specified type and window. If it finds a match,
XCheckTypedWindowEvent removes the event from the queue, copies it into
the specified XEvent structure, and returns True. The other events in
the queue are not discarded. If the event is not available,
XCheckTypedWindowEvent returns False, and the output buffer will have
been flushed.
SEE ALSO
XAnyEvent(3), XIfEvent(3), XPutBackEvent(3), XSendEvent(3)
Xlib - C Language X Interface