+ be specified, right from the beginning. This also applies to
+ sockets. Effectively this means that all invocations to:
+
+ a) open() must get O_CLOEXEC passed
+ b) socket() and socketpair() must get SOCK_CLOEXEC passed
+ c) recvmsg() must get MSG_CMSG_CLOEXEC set
+ d) F_DUPFD_CLOEXEC should be used instead of F_DUPFD, and so on