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// 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)
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