Windows answers a SYN to a closed port with a RST and then retransmits
the SYN, so connect to a closed loopback port takes about 2 s before
ECONNREFUSED; FreeBSD fails at once. PS5VR (PPSA99177) makes about 33
such connects to 127.0.0.1:17600 and reaches its home screen 45 s late.
When no socket listens on the destination port (GetExtendedTcpTable),
a loopback connect now sets SIO_TCP_INITIAL_RTO with no SYN
retransmissions and fails at once. A port with a listener keeps the
retransmissions: Windows also answers a SYN to a full accept backlog
with a RST, and the retransmission connects once the server accepts,
as the console's does after FreeBSD drops the SYN.
guest_refused_connect requires ECONNREFUSED in under a second for a
closed port through libkernel connect and sceNetConnect, and a second
connect to a listener with backlog 1 to succeed once the server accepts
the first, through both.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
