system call suspends the calling process until at least one of the
specified asynchronous I/O requests have completed, a signal is
delivered, or the
is an array of
pointers to asynchronous I/O requests.
Array members containing
null pointers will be silently ignored.
is not a null pointer, it specifies a maximum interval to suspend.
is a null pointer, the suspend blocks indefinitely.
To effect a
should point to a zero-value timespec structure.