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XALLOWDEVICEEVENTS(3)                                    XALLOWDEVICEEVENTS(3)

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.

       o   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.

       o   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.

       o   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.

       o   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.

       o   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.

       o   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(3)

                                  09/15/2021             XALLOWDEVICEEVENTS(3)