Three rules the bridge has always promised, none of which anything committed
could see.
The timeout was the structural one. Both scenarios end their waits with a close,
so the duration the bridge waits on governed nothing either of them observes: a
hard-coded 2000 ms survived the whole Linux matrix and Windows, and a host asking
for five seconds would have got two forever with nothing reporting it. The fix is
not another entry at another constant. A timeout's only observable is how long
the call takes, so `polltimeout` lets an idle runtime's poll be ended by its own
timeout and measures it, twice at different values, because no single constant
sits in both bands. The seam's hold moves behind that too: it parks only a call
the wait woke, so a poll whose own timeout expired is on its way out rather than
held there by the fixture and counted as the bridge's doing.
The refusal during a close (the header's section 4) had no scenario at all. A
call admitted after the closer has begun increments the in-flight count behind a
wait that has already read it. `latecall` holds the close open with the seam and
makes a call into it.
And the two-phase poll was written off as needing a listener, a credential and a
connection. It needs a closed loopback port: the failure always carries a reason,
which is an 87-byte payload, in about a millisecond. Moving the pop above the
copy crashes on both targets.
18 killed, 0 survived, 0 skipped on linux-x64; 16 killed, 0 survived on
win32-x64, where the two ThreadSanitizer entries are honestly skipped. Both runs
restored the source to the same sha256, b163cab7d48ebc93.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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