An nng_aio is an opaque structure used in conjunction with
asynchronous I/O operations.
Every asynchronous operation uses one of these structures, each of which
can only be used with a single operation at a time.
Asynchronous operations are performed without blocking calling application threads. Instead the application registers a callback function to be executed when the operation is complete (whether successfully or not). This callback will be executed exactly once.
The asynchronous I/O framework also supports cancellation of
operations that are already in progress
(see nng_aio_cancel()), as well setting a maximum
timeout for them to complete within
(see nng_aio_set_timeout()).
It is also possible to initiate an asynchronous operation, and wait for it to
complete using nng_aio_wait().
These structures are created using the nng_aio_alloc(),
and destroyed using nng_aio_free().
nng_aio_abort(3), nng_aio_alloc(3), nng_aio_cancel(3), nng_aio_count(3), nng_aio_free(3), nng_aio_get_input(3), nng_aio_get_msg(3), nng_aio_get_output(3), nng_aio_result(3), nng_aio_set_input(3), nng_aio_set_iov(3), nng_aio_set_msg(3), nng_aio_set_timeout(3), nng_aio_stop(3), nng_aio_wait(3), nng_strerror(3), nng_aio(5), nng(7)