{
    "mode": "man",
    "parameter": "UDPLITE",
    "section": "7",
    "url": "https://www.chedong.com/phpMan.php/man/UDPLITE/7/json",
    "generated": "2026-05-30T06:05:09Z",
    "synopsis": "",
    "sections": {
        "NAME": {
            "content": "udplite - Lightweight User Datagram Protocol\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "",
            "subsections": [
                {
                    "name": "#include <sys/socket.h>",
                    "content": "sockfd = socket(AFINET, SOCKDGRAM, IPPROTOUDPLITE);\n"
                }
            ]
        },
        "DESCRIPTION": {
            "content": "This  is an implementation of the Lightweight User Datagram Protocol (UDP-Lite), as described\nin RFC 3828.\n\nUDP-Lite is an extension of UDP (RFC 768) to support variable-length checksums.  This has ad‐\nvantages for some types of multimedia transport that may be able to make use of slightly dam‐\naged datagrams, rather than having them discarded by lower-layer protocols.\n\nThe variable-length checksum coverage is set via a setsockopt(2) option.  If this  option  is\nnot  set,  the  only difference from UDP is in using a different IP protocol identifier (IANA\nnumber 136).\n\nThe UDP-Lite implementation is a full extension of udp(7)—that is, it shares the same API and\nAPI behavior, and in addition offers two socket options to control the checksum coverage.\n",
            "subsections": [
                {
                    "name": "Address format",
                    "content": "UDP-Litev4 uses the sockaddrin address format described in ip(7).  UDP-Litev6 uses the sock‐\naddrin6 address format described in ipv6(7).\n"
                },
                {
                    "name": "Socket options",
                    "content": "To set or get a UDP-Lite socket option, call getsockopt(2) to read or setsockopt(2) to  write\nthe  option  with  the  option  level  argument set to IPPROTOUDPLITE.  In addition, all IP‐‐\nPROTOUDP socket options are valid on a UDP-Lite socket.  See udp(7) for more information.\n\nThe following two options are specific to UDP-Lite.\n\nUDPLITESENDCSCOV\nThis option sets the sender checksum coverage and takes an int  as  argument,  with  a\nchecksum coverage value in the range 0..2^16-1.\n\nA  value  of  0 means that the entire datagram is always covered.  Values from 1-7 are\nillegal (RFC 3828, 3.1) and are rounded up to the minimum coverage of 8.\n\nWith regard to IPv6 jumbograms (RFC 2675), the UDP-Litev6 checksum coverage is limited\nto  the  first  2^16-1  octets,  as  per  RFC 3828,  3.5.  Higher values are therefore\nsilently truncated to 2^16-1.  If in doubt, the current coverage value can  always  be\nqueried using getsockopt(2).\n\nUDPLITERECVCSCOV\nThis  is  the receiver-side analogue and uses the same argument format and value range\nas UDPLITESENDCSCOV.  This option is not required to  enable  traffic  with  partial\nchecksum  coverage.   Its  function  is that of a traffic filter: when enabled, it in‐\nstructs the kernel to drop all packets which have a coverage less than  the  specified\ncoverage value.\n\nWhen  the  value  of  UDPLITERECVCSCOV  exceeds the actual packet coverage, incoming\npackets are silently dropped, but may generate a warning message in the system log.\n"
                }
            ]
        },
        "ERRORS": {
            "content": "All errors documented for udp(7) may be returned.  UDP-Lite does not add further errors.\n",
            "subsections": []
        },
        "FILES": {
            "content": "/proc/net/snmp\nBasic UDP-Litev4 statistics counters.\n\n/proc/net/snmp6\nBasic UDP-Litev6 statistics counters.\n",
            "subsections": []
        },
        "VERSIONS": {
            "content": "UDP-Litev4/v6 first appeared in Linux 2.6.20.\n",
            "subsections": []
        },
        "BUGS": {
            "content": "Where glibc support is missing, the following definitions are needed:\n\n#define IPPROTOUDPLITE     136\n#define UDPLITESENDCSCOV  10\n#define UDPLITERECVCSCOV  11\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "ip(7), ipv6(7), socket(7), udp(7)\n\nRFC 3828 for the Lightweight User Datagram Protocol (UDP-Lite).\n\nDocumentation/networking/udplite.txt in the Linux kernel source tree\n",
            "subsections": []
        },
        "COLOPHON": {
            "content": "This page is part of release 5.10 of the Linux  man-pages  project.   A  description  of  the\nproject,  information about reporting bugs, and the latest version of this page, can be found\nat https://www.kernel.org/doc/man-pages/.\n\n\n\nLinux                                        2017-09-15                                   UDPLITE(7)",
            "subsections": []
        }
    },
    "summary": "udplite - Lightweight User Datagram Protocol",
    "flags": [],
    "examples": [],
    "see_also": [
        {
            "name": "ip",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/ip/7/json"
        },
        {
            "name": "ipv6",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/ipv6/7/json"
        },
        {
            "name": "socket",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/socket/7/json"
        },
        {
            "name": "udp",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/udp/7/json"
        }
    ]
}