The fd-passing-era surface — recvmsg with the msghdr/cmsghdr/iovec struct family, raw read/write, ioctl/winsize, the fcntl non-blocking helpers — had no callers since the daemon dissolution (D-56); NativePty binds its own symbols. What remains is what's actually consumed: socketpair + close (the ClideTestApp harness), errno, the poll event bits, and the two signal numbers. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>