XAllowDeviceEvents(3X11) X FUNCTIONS XAllowDeviceEvents(3X11)NAME
XAllowDeviceEvents - release queued events
SYNTAX
XAllowDeviceEvents(display, device, event_mode, time)
Display *display;
XDevice *device;
int event_mode;
Time time;
ARGUMENTS
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, Syn‐
cAll, 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 speci‐
fied 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 pro‐
cessing for that device continues as usual. If the device
is frozen multiple times by the client on behalf of multi‐
ple separate grabs, AsyncThisDevice thaws for all. Async‐
ThisDevice 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 nor‐
mally 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 GrabDeviceBut‐
ton or from a previous AllowDeviceEvents with mode Sync‐
ThisDevice, 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 XOpen‐
InputDevice. 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 ALSOXGrabDevice(3X11)
Programming With Xlib
X Version 11 Release 6 XAllowDeviceEvents(3X11)
