inet6_opt_append(3)inet6_opt_append(3)NAMEinet6_opt_append - Return the length of an IPv6 extension header with a
new option and append the option
SYNOPSIS
#include <netinet/ip6.h>
int inet6_opt_append(
void *extbuf,
size_t extlen,
int prevlen,
uint8_t type,
size_t len,
uint_t align,
void **databufp );
LIBRARY
Standard C Library (libc)
PARAMETERS
Points to a buffer that contains an extension header. This is either a
valid pointer or a NULL pointer. Specifies the length of the extension
header to initialize. Valid values are 0 if extbufequals 0, a value
returned by inet6_opt_finish(), or any number that is a multiple of 8.
Specifies the length of the existing extension header. Obtain this
value from a prior call to inet6_opt_init() or inet6_opt_append().
Specifies the type of option. Valid values range from 2 to 255, inclu‐
sive, excluding 194. Specifies the length of the option data, exclud‐
ing the option type and option length fields. Valid values range from 0
to 255, inclusive. Specifies the alignment of the option. Valid values
are 1, 2, 4, and 8. Points to a buffer that contains the option data.
DESCRIPTION
The inet6_opt_append() function when called with extbuf as a NULL
pointer and extlen as 0, returns the updated number of bytes in an
extension header.
If you specify extbuf as a valid pointer and valid len and align param‐
eters, the function returns the same information as in the previous
case, but also inserts the pad option, initializes the type and length
fields, and returns a pointer to the location for the option content.
After you call inet6_opt_append(), you can then use the databuf
directly or call inet6_opt_set_val() to specify the option contents.
RETURN VALUES
Upon successful completion, the inet6_opt_append() function returns the
updated number of bytes in an extension header. Upon failure, it
returns a -1.
SEE ALSO
Functions: inet6_opt_find(3), inet6_opt_finish(3),
inet6_opt_get_val(3), inet6_opt_init(3), inet6_opt_next(3),
inet6_opt_set_val(3).
Network Programmer's Guide
inet6_opt_append(3)
