SOCK_IO_RECV_LOCK
while (SOCK_IO_RECV_LOCK(so, 0) == EWOULDBLOCK) {
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
error = SOCK_IO_RECV_LOCK(so, SBL_WAIT);
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR);
error = SOCK_IO_RECV_LOCK(so, SBL_WAIT);
error = SOCK_IO_RECV_LOCK(so_src, 0);
error = SOCK_IO_RECV_LOCK(so_src, SBL_WAIT | SBL_NOINTR);
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR);
error = SOCK_IO_RECV_LOCK(old_so, waitflags);
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(in_flags));
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));