iv_task_unregister register, respectively unregister, a task with the current threads
ivykis event loop.
iv_task_registered on a task returns true if that task is currently registered with ivykis.
A task is like a timer, but with an immediate timeout. When a task
is registered, unless it is unregistered again first, the callback
function specified by
->handler is guaranteed to be called once, in the thread that the task was
registered in, some time after control returns to the ivykis main
loop but before ivykis will sleep for more events, with
->cookie as its first and sole argument. When this happens, the task is
Tasks are mainly used for scheduling code for execution where it is not
appropriate to directly run that code in the calling context (for
example, because the current context might be run as a callback function
where the caller expects certain conditions to remain invariant after
the callback completes).
The application is allowed to change the
->handler members at any time.
struct iv_task can only be registered in one thread at a time, and a task can only
be unregistered in the thread that it was registered from.
There is no limit on the number of tasks registered at once.
for programming examples.