XAllowDeviceEvents(3X11)XAllowDeviceEvents(3X11)NAMEXAllowDeviceEvents - release queued events
SYNOPSIS
XAllowDeviceEvents(display, device, event_mode, time)
Display *display;
XDevice *device;
int event_mode;
Time time;
ARGUMENTS
Specifies the connection to the X server. Specifies the device from
which events are to be allowed. Specifies the event mode. You can pass
AsyncThisDevice, SyncThisDevice, ReplayThisDevice, AsyncOtherDevices,
SyncAll, or AsyncAll. Specifies the time. You can pass either a time‐
stamp 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. 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. AsyncThis‐
Device has no effect if the specified device is not frozen by the
client, but the device need not be grabbed by the client. If the spec‐
ified device is frozen and actively grabbed by the client, event pro‐
cessing 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. SyncThisDe‐
vice has no effect if the specified device is not frozen by the client
or is not grabbed by the client. 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 SyncThisDevice, but
not from a GrabDevice), the grab is released and that event is com‐
pletely reprocessed. This time, however, the request ignores any pas‐
sive 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. If the remaining devices are frozen by the client, event pro‐
cessing for them continues as usual. If the other devices are frozen
multiple times by the client on behalf of multiple grabs, AsyncOtherDe‐
vices "thaws" for all. AsyncOtherDevices has no effect if the devices
are not frozen by the client. 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 sub‐
sequent freeze for SyncAll will only freeze each device once. If all
devices are frozen by the client, event processing for all devices con‐
tinues 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
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. An invalid mode was specified on the request.
SEE ALSOXGrabDevice(3X11)
Programming With Xlib
XAllowDeviceEvents(3X11)
