struct msghdr mh = {};
struct cmsghdr *cmsg;
struct iovec iov;
- int ms = 0, r;
- ssize_t l;
+ ssize_t ms, l;
+ int r;
assert(m);
assert(fd >= 0);
assert(ret);
- r = ioctl(fd, FIONREAD, &ms);
- if (r < 0)
- return -errno;
+ ms = next_datagram_size_fd(fd);
if (ms < 0)
- return -EIO;
+ return ms;
r = dns_packet_new(&p, protocol, ms);
if (r < 0)