udplite - Lightweight User Datagram Protocol

       Where glibc support is missing, the following definitions are needed:

           #define IPPROTO_UDPLITE     136
           #define UDPLITE_SEND_CSCOV  10
           #define UDPLITE_RECV_CSCOV  11

       This is an implementation of the Lightweight User Datagram Protocol (UDP-Lite), as described in RFC 3828.

       UDP-Lite  is an extension of UDP (RFC 768) to support variable-length checksums.  This has advantages for
       some types of multimedia transport that may be able to make use of  slightly  damaged  datagrams,  rather
       than having them discarded by lower-layer protocols.

       The  variable-length checksum coverage is set via a setsockopt(2) option.  If this option is not set, the
       only difference from UDP is in using a different IP protocol identifier (IANA number 136).

       The UDP-Lite implementation is a full extension of udp(7)—that  is,  it  shares  the  same  API  and  API
       behavior, and in addition offers two socket options to control the checksum coverage.

   Addressformat
       UDP-Litev4  uses  the  sockaddr_in  address  format described in ip(7).  UDP-Litev6 uses the sockaddr_in6
       address format described in ipv6(7).

   Socketoptions
       To set or get a UDP-Lite socket option, call getsockopt(2) to read or setsockopt(2) to write  the  option
       with  the  option level argument set to IPPROTO_UDPLITE.  In addition, all IPPROTO_UDP socket options are
       valid on a UDP-Lite socket.  See udp(7) for more information.

       The following two options are specific to UDP-Lite.

       UDPLITE_SEND_CSCOV
              This option sets the sender checksum coverage and takes  an  int  as  argument,  with  a  checksum
              coverage value in the range 0..2^16-1.

              A  value  of  0  means  that  the  entire datagram is always covered.  Values from 1-7 are illegal
              (RFC 3828, 3.1) and are rounded up to the minimum coverage of 8.

              With regard to IPv6 jumbograms (RFC 2675), the UDP-Litev6 checksum  coverage  is  limited  to  the
              first  2^16-1  octets,  as  per  RFC 3828, 3.5.  Higher values are therefore silently truncated to
              2^16-1.  If in doubt, the current coverage value can always be queried using getsockopt(2).

       UDPLITE_RECV_CSCOV
              This is the receiver-side  analogue  and  uses  the  same  argument  format  and  value  range  as
              UDPLITE_SEND_CSCOV.  This option is not required to enable traffic with partial checksum coverage.
              Its  function  is  that  of  a  traffic  filter: when enabled, it instructs the kernel to drop all
              packets which have a coverage less than the specified coverage value.

              When the value of UDPLITE_RECV_CSCOV exceeds the actual  packet  coverage,  incoming  packets  are
              silently dropped, but may generate a warning message in the system log.

       All errors documented for udp(7) may be returned.  UDP-Lite does not add further errors.

/proc/net/snmp
              Basic UDP-Litev4 statistics counters.

       /proc/net/snmp6
              Basic UDP-Litev6 statistics counters.

       udplite - Lightweight User Datagram Protocol

ip(7), ipv6(7), socket(7), udp(7)

       RFC 3828 for the Lightweight User Datagram Protocol (UDP-Lite).

       Documentation/networking/udplite.txt in the Linux kernel source tree

Linux man-pages 6.9.1                              2024-05-02                                         udplite(7)

#include<sys/socket.h>sockfd=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDPLITE);

       UDP-Litev4/v6 first appeared in Linux 2.6.20.