IPV6_RTHDR(2const) — Linux manual page

IPV6_RTHDR(2const)                                     IPV6_RTHDR(2const)

NAME         top

       IPV6_RTHDR, IPV6_AUTHHDR, IPV6_DSTOPTS, IPV6_HOPOPTS,
       IPV6_FLOWINFO, IPV6_HOPLIMIT - set the delivery of control
       messages for incoming datagrams containing extension headers

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <netinet/in.h>  /* Definition of IP* constants */
       #include <sys/socket.h>

       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_RTHDR,
                      const int *enable, sizeof(int));
       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_AUTHHDR,
                      const int *enable, sizeof(int));
       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_DSTOPTS,
                      const int *enable, sizeof(int));
       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_HOPOPTS,
                      const int *enable, sizeof(int));
       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_FLOWINFO,
                      const int *enable, sizeof(int));
       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_HOPLIMIT,
                      const int *enable, sizeof(int));

DESCRIPTION         top

       Set delivery of control messages for incoming datagrams containing
       extension headers from the received packet.

       IPV6_RTHDR
              delivers the routing header.

       IPV6_AUTHHDR
              delivers the authentication header.

       IPV6_DSTOPTS
              delivers the destination options.

       IPV6_HOPOPTS
              delivers the hop options.

       IPV6_FLOWINFO
              delivers an integer containing the flow ID.

       IPV6_HOPLIMIT
              delivers an integer containing the hop count of the packet.

       The control messages have the same type as the socket option.

       All these header options can also be set for outgoing packets by
       putting the appropriate control message into the control buffer of
       sendmsg(2).

       Allowed only for SOCK_DGRAM or SOCK_RAW sockets.

ERRORS         top

       See IPPROTO_IPV6(2const).  See setsockopt(2).  See ipv6(7).

SEE ALSO         top

       IPPROTO_IPV6(2const), setsockopt(2), cmsg(3), ipv6(7)

COLOPHON         top

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Linux man-pages 6.18            2025-12-02             IPV6_RTHDR(2const)

Pages that refer to this page: IPPROTO_IPV6(2const)

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