The guest socket layer relies on a few Linux calls:
- The equeue wait uses poll with the timeout rounded up to a millisecond;
macOS has no ppoll.
- A readable stream socket whose peer closed is reported with POLLHUP by
peeking one byte; macOS has no POLLRDHUP.
- FIONREAD on a datagram socket, and the byte count that fstat and kevent
report for it, is SO_NREAD, the size of the next datagram; macOS adds the
source address to FIONREAD.
- socketpair throws for SOCK_SEQPACKET, which has no AF_UNIX pair on macOS.
- gethostbyname replaces gethostbyname_r, which macOS lacks.
The UDP test sends on its connected socket without an address, as #7475
does, because macOS, like FreeBSD, fails sendto with an address on a
connected socket with EISCONN. The log test uses a datagram pair with
enlarged buffers instead of SOCK_SEQPACKET.
mugurc
7701a9b9da