getpeername/getsockname/recvfrom/accept should maybe return the untruncated size
Linux's documentation says it returns the untruncated size (even if truncation occurred) and the documentation for other operating systems and even POSIX are somewhat ambiguous.
https://austingroupbugs.net/view.php?id=464 introduced the current unclear POSIX language and seems to intend the untruncated size to be provided.
This behavior should be os-test'd to resolve what behavior should be implemented. Right now Sortix returns the truncated size out of caution.