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Re: Select call of libcurl returns without connecting

From: A. Craig West <acraigwest_at_gmail.com>
Date: Thu, 10 Dec 2009 15:48:24 -0500

2009/12/9 <centrio_at_gmail.com>:
> I have developed an application that uses libcurl.
> I give command "set http_proxy=" and then run libcurl application.
> Now when I give a URL that represents 193.88.125.20,to my libcurl
> application, its taking more time to route I guess. But if I have connected
> to the internet (any URL) before connecting using libcurl, it connects much
> early. Is it that libcurl request is taking more time for its first request?
> Does Some initialization or routing is takes time in above scenario??
>
> I have also observed that if ther is a url ABC, then If i connect it using
> my application it does not connect immediately, but If i first run it
> through media player, internet explorer, and then try using my application,
> it works immediately. What could be the issue?

I suspect in both of these cases the extra delays are caused by DNS
lookups. I would have to check the code, but it seems likely that even
when you specify a raw ip address, it attempts to do a DNS look-up
first, and then tries it directly. On subsequent calls, the result of
the lookup is probably cached at your router.
-Craig
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Received on 2009-12-10