Append IPv6 hop-by-hop or destination options into ancillary data object
#include <netinet/in.h> u_int8_t * inet6_option_alloc(struct cmsghdr *cmsg, int datalen, int multx, int plusy);
Use the -l socket option to qcc to link against this library.
This inet6_option_alloc() function appends a hop-by-hop option or a destination option into an ancillary data object that has been initialized by inet6_option_init().
The difference between this function and inet6_option_append() is that the latter copies the contents of the previously built option into the ancillary data object. This function returns a pointer to the space in the data object where the option's type-length-value or TLV must then be built by the caller.
A pointer to the 8-bit option type field that starts the option, or NULL if an error has occurred.
inet6_option_append(), inet6_option_find(), inet6_option_init(), inet6_option_next(), inet6_option_space()