XSelectExtensionEvent

Langue: en

Autres versions - même langue

Version: 08/04/2010 (fedora - 01/12/10)

Section: 3 (Bibliothèques de fonctions)

Sommaire

NAME

XSelectExtensionEvent, XGetSelectedExtensionEvents - select extension events, get the list of currently selected extension events

SYNOPSIS

 #include <X11/extensions/XInput.h>
 

 XSelectExtensionEvent( Display *display,
                        Window w,
                        XEventClass *event_list,
                        int event_count);
 

 XGetSelectedExtensionEvents( Display *display,
                              Window w,
                              int *this_client_event_count_return,
                              XEventClass **this_client_event_list_return,
                              int *all_clients_event_count_return,
                              XEventClass **all_clients_event_list_return);
 

 display
        Specifies the connection to the X server.
 

 w
        Specifies the window whose events you are interested in.
 

 event_list
        Specifies the list of event classes that describe the
        events you are interested in.
 

 event_count
        Specifies the count of event classes in the event list.
 

 this_client_event_count_return
        Returns the count of event classes selected by this
        client.
 

 this_client_event_list_return
        Returns a pointer to the list of event classes selected
        by this client.
 

 all_clients_event_count_return
        Returns the count of event classes selected by all
        clients.
 

 all_clients_event_list_return
        Returns a pointer to the list of event classes selected
        by all clients.

DESCRIPTION

 The XSelectExtensionEvent request causes the X server to report
 the events associated with the specified list of event classes.
 Initially, X will not report any of these events. Events are
 reported relative to a window. If a window is not interested in
 a device event, it usually propagates to the closest ancestor
 that is interested, unless the do_not_propagate mask prohibits
 it.
 

 Multiple clients can select for the same events on the same
 window with the following restrictions:
   * Multiple clients can select events on the same window
     because their event masks are disjoint. When the X server
     generates an event, it reports it to all interested
     clients.
   * Only one client at a time can select a DeviceButtonPress
     event with automatic passive grabbing enabled, which is
     associated with the event class DeviceButtonPressGrab. To
     receive DeviceButtonPress events without automatic passive
     grabbing, use event class DeviceButtonPress but do not
     specify event class DeviceButtonPressGrab.
 

 The server reports the event to all interested clients.
 

 Information contained in the XDevice structure returned by
 XOpenDevice is used by macros to obtain the event classes that
 clients use in making XSelectExtensionEvent requests. Currently
 defined macros include DeviceKeyPress, DeviceKeyRelease,
 DeviceButtonPress, DeviceButtonRelese, DeviceMotionNotify,
 DeviceFocusIn, DeviceFocusOut, ProximityIn, ProximityOut,
 DeviceStateNotify, DeviceMappiingNotify, ChangeDeviceNotify,
 DevicePointerMotionHint, DeviceButton1Motion,
 DeviceButton2Motion, DeviceButton3Motion, DeviceButton4Motion,
 DeviceButton5Motion, DeviceButtonMotion, DeviceOwnerGrabButton,
 DeviceButtonPressGrab, and NoExtensionEvent.
 

 To obtain the proper event class for a particular device, one
 of the above macros is invoked using the XDevice structure for
 that device. For example,
              DeviceKeyPress (*device, type, eventclass);
 

 returns the DeviceKeyPress event type and the eventclass for
 selecting DeviceKeyPress events from this device.
 

 XSelectExtensionEvent can generate a BadWindow or BadClass
 error. The XGetSelectedExtensionEvents request reports the
 extension events selected by this client and all clients for
 the specified window. This request returns pointers to two
 XEventClass arrays. One lists the input extension events
 selected by this client from the specified window. The other
 lists the event classes selected by all clients from the
 specified window. You should use XFree to free these two
 arrays.
 

 XGetSelectedExtensionEvents can generate a BadWindow error.

DIAGNOSTICS

 BadWindow
        A value for a Window argument does not name a defined
        window.
 

 BadClass
        A value for an XEventClass is invalid.