o Describe passing file descriptors as separate section.
- Descriptors can be passed through any protocol of the UNIX family,
not SOCK_STREAM and SOCK_SEQPACKET only. [1]
o Describe socket options as separate section.
- Move LOCAL_PEERCRED option to this section.
- Describe struct xucred.
- In LOCAL_CREDS section mention that credentials
are passed only on the first read on non-datagram
sockets.
o Xref all mentioned system calls.
Noticed by: Igor Sysoev [1]
dc169f2862