void gre_io_close( gre_io_t * handle )
Close an io connection. Any pending clients will return with an error on their pending actions. This call should be serialized with other clients that are referencing the same
gre_io_t handle to avoid race conditions. A common technique for closing handles where a receiving thread may be blocked on the handle is to generate a termination event and have the receiving thread perform the close and channel cleanup.
Parameters: handle A valid handle created with gre_io_open()