Adds an IPv6 address to the routing header under construction.
    Format
      #include  <in6.h>
      int inet6_rth_add  ( void *bp, const struct in6_addr *addr );

1  –  Arguments

 bp
    Points to a buffer that is to contain an IPv6 routing header.
 addr
    Points to an IPv6 address to add to the routing header.

2  –  Description

    This function adds an IPv6 address to the end of the routing
    header under construction. The address pointed to by addr cannot
    be an IPv6 V4-mapped address or an IPv6 multicast address.
    The function increments the ip6r0_segleft member in the ip6_
    rthdr0 structure. The ip6_rthdr0 structure is defined in the
    IP6.H header file.
    Only routing header type 0 is supported.

3  –  Return Values

    x                  Upon successful completion, the inet6_rth_
                       add() function returns 0 (zero).
    -1                 Failure