Maintained by: NLnet Labs

[Unbound-users] get ttl in libunbound?

W.C.A. Wijngaards
Mon Nov 23 12:08:30 CET 2009

Hash: SHA1


Not sure what to do about this.  Unbound already returns the TTL inside
the 'raw packet data' chunk in the result.  I understand that that is
not really easy, since you need (say) ldns_wire2pkt to get at that TTL.

Is this bloat or is this useful?

Best regards,

On 11/14/2009 06:08 AM, David Hubbard wrote:
> Hi all,
> This patch adds a call to free(ttl) that balances the call to
> calloc(). The previous patch creates a memory leak.
> This patch also moves 'unsigned *ttl' to the end of struct ub_result,
> so that binaries linked against will still work.
> David
> On Fri, Nov 13, 2009 at 4:18 PM, David Hubbard
> <david.c.hubbard at> wrote:
>> Hi Ondrej,
>> On Fri, Nov 13, 2009 at 4:10 PM, Ondřej Surý <ondrej at> wrote:
>>> On Fri, Nov 13, 2009 at 23:55, David Hubbard <david.c.hubbard at> wrote:
>>>> Hi all,
>>>> I'd like to get the TTL value for a DNS request. I looked at what it
>>>> would take to add this to struct ub_result and it doesn't look too
>>>> difficult - patch attached.
>>> Please don't change the existing API. In this case it could be solved
>>> just by recompiling all dependant programs, but generally changing
>>> existing API causes a lot of troubles (beware not adding new functions
>>> and data types - but really changing existing functions).
>> I agree - this patch breaks the ABI. I don't think this is an urgent
>> matter, so would it be acceptable to put this in the queue for
>> whenever the next major API changes happen?
>> I do want to use the full validating resolver (especially dnssec). I
>> also find the libunbound interface simpler, so my code is easy to
>> read. I'm trying to replace code that used a different dns resolver
>> library that has gone dormant and doesn't have dnssec support.
>> One possibility is to place unsigned* ttl at the end of struct
>> ub_result - then existing applications would not break. I think it
>> "looks nicer" where it is. Either way, it doesn't really matter.
>> Thanks for your consideration,
>> David
>> _______________________________________________
>> Unbound-users mailing list
>> Unbound-users at

Version: GnuPG v1.4.9 (GNU/Linux)
Comment: Using GnuPG with Fedora -