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// SPDX-License-Identifier: GPL-2.0
// Verify behavior for the sequence: remote side sends FIN, then we close().
// Since the remote side (client) closes first, we test our LAST_ACK code path.
`./defaults.sh`
// Initialize a server socket.
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,nop,wscale 7>
+0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
+0 < . 1:1(0) ack 1 win 257
+0 accept(3, ..., ...) = 4
// Client closes first.
+.01 < F. 1:1(0) ack 1 win 257
+0 > . 1:1(0) ack 2
// App notices that client closed.
+0 read(4, ..., 1000) = 0
// Then we close.
+.01 close(4) = 0
+0 > F. 1:1(0) ack 2
// Client ACKs our FIN.
+.01 < . 2:2(0) ack 2 win 257
// Verify that we send RST in response to any incoming segments
// (because the kernel no longer has any record of this socket).
+.01 < . 2:2(0) ack 2 win 257
+0 > R 2:2(0)
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