+++ /dev/null
-.\" Copyright (c) 2008 by Gerrit Renker <gerrit@erg.abdn.ac.uk>
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" $Id: udplite.7,v 1.12 2008/07/23 15:22:22 gerrit Exp gerrit $
-.\"
-.TH UDPLITE 7 2014-07-08 "Linux" "Linux Programmer's Manual"
-.SH NAME
-udplite \- Lightweight User Datagram Protocol
-.SH SYNOPSIS
-.B #include <sys/socket.h>
-.br
-.\" FIXME . see #defines under `BUGS',
-.\" when glibc supports this, add
-.\" #include <netinet/udplite.h>
-.sp
-.B sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDPLITE);
-.SH DESCRIPTION
-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
-.BR setsockopt (2)
-option.
-If this option is not set, the only difference to UDP is
-in using a different IP protocol identifier (IANA number 136).
-
-The UDP-Lite implementation is a full extension of
-.BR udp (7)\(emthat
-is, it shares the same API and API behavior, and in addition
-offers two socket options to control the checksum coverage.
-.SS Address format
-UDP-Litev4 uses the
-.I sockaddr_in
-address format described in
-.BR ip (7).
-UDP-Litev6 uses the
-.I sockaddr_in6
-address format described in
-.BR ipv6 (7).
-.SS Socket options
-To set or get a UDP-Lite socket option, call
-.BR getsockopt (2)
-to read or
-.BR setsockopt (2)
-to write the option with the option level argument set to
-.BR IPPROTO_UDPLITE .
-In addition, all
-.B IPPROTO_UDP
-socket options are valid on a UDP-Lite socket.
-See
-.BR udp (7)
-for more information.
-
-The following two options are specific to UDP-Lite.
-.TP
-.BR UDPLITE_SEND_CSCOV
-This option sets the sender checksum coverage and takes an
-.I 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
-.BR getsockopt (2).
-.TP
-.BR UDPLITE_RECV_CSCOV
-This is the receiver-side analogue and uses the same argument format
-and value range as
-.BR 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
-.I less
-than the specified coverage value.
-
-When the value of
-.B UDPLITE_RECV_CSCOV
-exceeds the actual packet coverage, incoming packets are silently dropped,
-but may generate a warning message in the system log.
-.\" SO_NO_CHECK exists and is supported by UDPv4, but is
-.\" commented out in socket(7), hence also commented out here
-.\".PP
-.\"Since UDP-Lite mandates checksums, checksumming can not be disabled
-.\"via the
-.\".B SO_NO_CHECK
-.\"option from
-.\".BR socket (7).
-.SH ERRORS
-All errors documented for
-.BR udp (7)
-may be returned.
-UDP-Lite does not add further errors.
-.SH FILES
-.I /proc/net/snmp
-\- basic UDP-Litev4 statistics counters.
-.br
-.I /proc/net/snmp6
-\- basic UDP-Litev6 statistics counters.
-.SH VERSIONS
-UDP-Litev4/v6 first appeared in Linux 2.6.20.
-.SH BUGS
-.\" FIXME . remove this section once glibc supports UDP-Lite
-Where glibc support is missing, the following definitions are needed:
-.in +4n
-.nf
-
-#define IPPROTO_UDPLITE 136
-.\" The following two are defined in the kernel in linux/net/udplite.h
-#define UDPLITE_SEND_CSCOV 10
-#define UDPLITE_RECV_CSCOV 11
-.fi
-.in
-.SH SEE ALSO
-.BR ip (7),
-.BR ipv6 (7),
-.BR socket (7),
-.BR udp (7)
-
-RFC\ 3828 for the Lightweight User Datagram Protocol (UDP-Lite).
-
-.I Documentation/networking/udplite.txt
-in the Linux kernel source tree
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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