IPV6_RTHDR(2const)                                          IPV6_RTHDR(2const)

NAME
       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
       Standard C library (libc, -lc)

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

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

Linux man-pages 6.17              2025-12-02                IPV6_RTHDR(2const)