| // SPDX-License-Identifier: GPL-2.0 | |
| `./defaults.sh` | |
| // Initialize connection | |
| 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 | |
| +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 | |
| +0 bind(3, ..., ...) = 0 | |
| +0 listen(3, 1) = 0 | |
| +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop> | |
| +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> | |
| +.1 < . 1:1(0) ack 1 win 32792 | |
| +0 accept(3, ..., ...) = 4 | |
| // Okay, we received nothing, and decide to close this idle socket. | |
| // We set TCP_USER_TIMEOUT to 3 seconds because really it is not worth | |
| // trying hard to cleanly close this flow, at the price of keeping | |
| // a TCP structure in kernel for about 1 minute ! | |
| +2 setsockopt(4, SOL_TCP, TCP_USER_TIMEOUT, [3000], 4) = 0 | |
| +0 close(4) = 0 | |
| +0 > F. 1:1(0) ack 1 | |
| +.3~+.400 > F. 1:1(0) ack 1 | |
| +.3~+.400 > F. 1:1(0) ack 1 | |
| +.6~+.800 > F. 1:1(0) ack 1 | |
| // We finally receive something from the peer, but it is way too late | |
| // Our socket vanished because TCP_USER_TIMEOUT was really small | |
| +0 < . 1:2(1) ack 1 win 32792 | |
| +0 > R 1:1(0) |