icmp6(7P)

NAME
     icmp6 - Internet Control Message Protocol

SYNOPSIS
     #include <sys/socket.h>
     #include <netinet/in.h>

     s = socket(AF_INET6, SOCK_RAW, proto);

DESCRIPTION
     ICMP6 is the error and control message protocol used by version 6 of the
     Internet protocol family.  It may be accessed through a "raw socket" for
     network monitoring and diagnostic functions.  The proto parameter to the
     socket call to create an ICMP6 socket is obtained from
     getprotobyname(3N).  ICMP6 sockets are connectionless, and are normally
     used with the sendto and recvfrom or sendmsg and recvmsg calls, though
     the connect(2) call may also be used to fix the destination for future
     packets (in which case the read(2) or recv(2) and write(2) or send(2)
     system calls may be used).

     Outgoing packets automatically have an IPv6 header prepended to them.
     The IPv6 header and extension headers of the incoming packets are
     available only as ancillary data in the msghdr argument of recvmsg(2).

DIAGNOSTICS
     A socket operation may fail with one of the following errors returned:

     [EISCONN]      when trying to establish a connection on a socket which
                    already has one, or when trying to send a datagram with
                    the destination address specified and the socket is
                    already connected;

     [ENOTCONN]     when trying to send a datagram, but no destination address
                    is specified, and the socket hasn't been connected;

     [ENOBUFS]      when the system runs out of memory for an internal data
                    structure;

     [EADDRNOTAVAIL]
                    when an attempt is made to create a socket with a network
                    address for which no network interface exists.

SEE ALSO
     send(2), recv(2), sendmsg(2), recvmsg(2), intro(3), inet6(7F), ip6(7P)