Out-of-band TCP messages are used for TCP data
transmission outside (outband) the inbound TCP
data. These packets are sent with an
"urgent pointer", but previously discarded.
Additionally, when using (e)poll a POLLPRI is
triggered when an interrupt signal is received
on GPIO capable systems such as the Raspberry Pi.
PR-URL: https://github.com/libuv/libuv/pull/1040
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>