lispdoc - results for +max-datagram-packet-size+

usocket:+max-datagram-packet-size+
Variable: The theoretical maximum amount of data in a UDP datagram. The IPv4 UDP packets have a 16-bit length constraint, and IP+UDP header has 28-byte. IP_MAXPACKET = 65535, /* netinet/ip.h */ sizeof(struct ip) = 20, /* netinet/ip.h */ sizeof(struct udphdr) = 8, /* netinet/udp.h */ 65535 - 20 - 8 = 65507 (But for UDP broadcast, the maximum message size is limited by the MTU size of the underlying link)