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Re: Random crash in Curl_resolv

From: Prasanna Vijapur - Sun Microsystems <>
Date: Fri, 18 Nov 2005 18:25:53 -0500

Hi Daniel,

Thanks for your reply.

Daniel Stenberg wrote:

> On Thu, 17 Nov 2005, Prasanna Vijapur - Sun Microsystems wrote:
>> My program crashes in Curl_resolv while trying to post the data. I am
>> using libcurl 7.14.0. This is multithreaded program and uses https.
> Does it crash at the same point all the time?

yes, it crashes in Curl_resolv at below point.
It is coming here from siglongjmp() in SIGALARM signal handler.
But I do not know why it is getting SIGBUS or sometimes SIGSEGV here.
(line number 390 hostip.c)
detected a multithreaded program
t_at_1 (l_at_1) terminated by signal BUS (invalid address alignment)
Current function is Curl_resolv
  390 failf(data, "name lookup timed out");

>> The IP address is provided in the url, Will linking with C-ares help me?
> No. When the IP-adress is given, libcurl won't resolve any name. It'll
> just instantly convert the given address and use that.
>> Even when ipaddress is provided, curl does the signal handling for
>> timing out the dns name resolve. line numbers:3374 to 3385 in url.c
>> Can this be avoided?
> With some clever re-arranging of the code it seems possible indeed.
> But why do you use signal-based timeouts if you don't want them to occur?
I will try setting CURLOPT_NOSIGNAL to true. I hope this will solve my

Thanks & Regards,
Received on 2005-11-19