xref: /xsrc/external/mit/libXi/dist/man/XAllowDeviceEvents.txt

XALLOWDEVICEEVENTS(libmansuffix)
================================

NAME
----

   XAllowDeviceEvents - release queued events

SYNOPSIS
------

   #include <X11/extensions/XInput.h>

   int XAllowDeviceEvents( Display *display,
                           XDevice *device,
                           int event_mode,
                           Time time);
   display
          Specifies the connection to the X server.

   device
          Specifies the device from which events are to be
          allowed.

   event_mode
          Specifies the event mode.You can pass AsyncThisDevice,
          SyncThisDevice, ReplayThisDevice, AsyncOtherDevices,
          SyncAll,or AsyncAll.

   time
          Specifies the time.You can pass either a timestamp or
          CurrentTime.

DESCRIPTION
-----------

The XAllowDeviceEvents function releases some queued events if
the client has caused a device to freeze. It has no effect if
the specified time is earlier than the last-grab time of the
most recent active grab for the client and device, or if the
specified time is later than the current X server time.

The following describes the processing that occurs depending on
what constant you pass to the event_mode argument.

   * AsyncThisDevice - If the specified device is frozen by the
   client, event processing for that device continues as usual. If
   the device is frozen multiple times by the client on behalf of
   multiple separate grabs, AsyncThisDevice thaws for
   all.AsyncThisDevice has no effect if the specified device is
   not frozen by the client, but the device need not be grabbed by
   the client.

   * SyncThisDevice - If the specified device is frozen and actively
   grabbed by the client, event processing for that device
   continues normally until the next key or button event is
   reported to the client. At this time, the specified device
   again appears to freeze. However, if the reported event causes
   the grab to be released, the specified device does not freeze.
   SyncThisDevice has no effect if the specified device is not
   frozen by the client or is not grabbed by the client.

   * ReplayThisDevice - If the specified device is actively grabbed by
   the client and is frozen as the result of an event having been
   sent to the client (either from the activation of a
   GrabDeviceButton or from a previous AllowDeviceEvents with mode
   SyncThisDevice, but not from a GrabDevice), the grab is
   released and that event is completely reprocessed. This time,
   however, the request ignores any passive grabs at or above
   (toward the root) that the grab-window of the grab just
   released. The request has no effect if the specified device is
   not grabbed by the client or if it is not frozen as the result
   of an event.

   * AsyncOtherDevices - If the remaining devices are frozen by the
   client, event processing for them continues as usual. If the
   other devices are frozen multiple times by the client on behalf
   of multiple grabs, AsyncOtherDevices "thaws" for all.
   AsyncOtherDevices has no effect if the devices are not frozen
   by the client.

   * SyncAll - If all devices are frozen by the client, event
   processing (for all devices) continues normally until the next
   button or key event is reported to the client for a grabbed
   device, at which time all devices again appear to freeze.
   However, if the reported event causes the grab to be released,
   then the devices do not freeze. If any device is still grabbed,
   then a subsequent event for it will still cause all devices to
   freeze. SyncAll has no effect unless all devices are frozen by
   the client. If any device is frozen twice by the client on
   behalf of two separate grabs, SyncAll thaws for both. A
   subsequent freeze for SyncAll will only freeze each device
   once.

   * AsyncAll - If all devices are frozen by the client, event
   processing for all devices continues normally. If any device is
   frozen multiple times by the client on behalf of multiple
   separate grabs, AsyncAll thaws for all. AsyncAll has no effect
   unless all devices are frozen by the client.

AsyncThisDevice, SyncThisDevice, and ReplayThisDevice have no
effect on the processing of events from the remaining
devices.AsyncOtherDevices has no effect on the processing of
events from the specified device. When the event_mode is
SyncAll or AsyncAll, the device parameter is ignored.

It is possible for several grabs of different devices by the
same or different clients to be active simultaneously. If a
device is frozen on behalf of any grab, no event processing is
performed for the device. It is possible for a single device to
be frozen because of several grabs. In this case, the freeze
must be released on behalf of each grab before events can again
be processed.

XAllowDeviceEvents can generate a BadDevice or BadValue error.

DIAGNOSTICS
-------------

   BadDevice
          An invalid device was specified. The specified device
          does not exist or has not been opened by this client via
          XOpenInputDevice. This error may also occur if the
          specified device is the X keyboard or X pointer device.

   BadValue
          An invalid mode was specified on the request.

SEE ALSO
--------

   XGrabDevice(libmansuffix)