Re: Query a DNS in C

phil-news-nospam_at_ipal.net
Date: 04/17/04 

Date: 17 Apr 2004 15:36:29 GMT

On 14 Apr 2004 21:08:00 GMT Jens.Toerring@physik.fu-berlin.de wrote:

| If it's just that the OP can have my code for whatever it's worth - it's
| supposed to take the name of the machine to send mail to (plus the name
| of the local machine) as input arguments and then to return the names of
| the machines prepared to accept mail for the remote machine successively
| (in order of priority). It doesn't do the talking with the DNS server
| directly, that's handled via the res_xxx() and dn_xxx() functions from
| libresolv, it just tries to make sense out of the DNS servers reply. So
| if the Christian is interested my email address isn't munged (just don't
| send me HTML formated mails, they tend to go to /dev/null directly).

Do you know of a library which can assist in doing the DNS queries in a
non-blocking way? It would be such that during any number of outstanding
queries, the process can continue to do other things, or wait in parallel
for these answers and other things it is waiting for. I would envision
(since I am thinking of writing my own if no good one can be found) that
such a library would have functions to set up a proper socket on which to
do waits (select or poll), functions to construct queries, a function to
do a non-blocking read/receive for any waiting answers, and functions to
take apart the answers. 

-- 
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| Phil Howard KA9WGN       | http://linuxhomepage.com/      http://ham.org/ |
| (first name) at ipal.net | http://phil.ipal.org/   http://ka9wgn.ham.org/ |
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