On 19/02/2021 17:19, Richard Hodges via Boost-users wrote:
The TCP/IP protocol was designed to work over unreliable networks, including sections that hop over radio links and dial-up telephone lines.
In a nutshell, the way the internet works is that packets are transmitted and it is assumed that they may or may not arrive at some timeĀ in the future. There are timeouts built in, but they are longer than you would probably want, on account of all the unreliable dial-ups between you and the other peer.
Therefore, to involve a timeout you need to run a timer in parallel with the send/receive operation and cancel the operation if the timeout occurs before the operation has completed.
It probably would be easier to set SO_KEEPALIVE on the socket, then it will close as soon as the physical connection disappears. This works for any kind of socket, no timeouts needed. Niall