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32 .Nd Lightweight User Datagram Protocol
38 .Fn socket AF_INET SOCK_DGRAM IPPROTO_UDPLITE
42 protocol provides a partial checksum which allows
43 corrupted packets to be transmitted to the receiving
45 This has advantages for some types of multimedia
46 transport that may be able to make use of slightly
47 damaged datagrams, rather than having them discarded
48 by lower-layer protocols.
51 supports a number of socket options which can be set with
55 .Bl -tag -width ".Dv UDPLITE_SEND_CSCOV"
56 .It Dv UDPLITE_SEND_CSCOV
57 This option sets the sender checksum coverage.
58 A value of zero indicates that the entire packet
59 is covered by the checksum.
60 A value of 1 to 7 must be discarded by the receiver.
61 .It Dv UDPLITE_RECV_CSCOV
62 This option is the receiver-side analogue.
63 It is truly optional, i.e. not required to enable traffic
64 with partial checksum coverage.
65 Its function is that of a traffic filter:
66 when enabled, it instructs the kernel to drop
67 all packets which have a coverage less than this value.
70 A socket operation may fail with one of the following errors returned:
73 when trying to establish a connection on a socket which
74 already has one, or when trying to send a datagram with the destination
75 address specified and the socket is already connected;
77 when trying to send a datagram, but
78 no destination address is specified, and the socket has not been
81 when the system runs out of memory for
82 an internal data structure;
85 is made to create a socket with a port which has already been
87 .It Bq Er EADDRNOTAVAIL
88 when an attempt is made to create a
89 socket with a network address for which no network interface