[zeromq-dev] Open file leak during DNS resolution while network is down (regression in libzmq-4.1.0 and libzmq-master) #1302

[Tomas Krajca]

Hi Peter,

It's actually really simple, I have posted example C code to github at 
https://github.com/zeromq/libzmq/issues/1302. Am I doing something wrong 
or is it that obvious?

There is no need for a poller or anything like that. It seems that DNS 
resolution during zmq_connect() somehow does not release the file handle 
if network is down.

Cheers,
Tomas

> Message: 19
> Date: Mon, 19 Jan 2015 10:32:47 +0100
> From: Pieter Hintjens <ph at imatix.com>
> Subject: Re: [zeromq-dev] Open file leak during DNS resolution while
> 	network is down (regression in libzmq-4.1.0 and libzmq-master) #1302
> To: ZeroMQ development list <zeromq-dev at lists.zeromq.org>
> Cc: Mark Burgess <mark at repositpower.com>
> Message-ID:
> 	<CADL5_shw3B+0YN4MYVCROEwufeH6_ThvxDKcw5c=vkfo4Dw5ew at mail.gmail.com>
> Content-Type: text/plain; charset=UTF-8
>
> Can your C++ programmer make a minimal test case in C that reproduces
> the problem?
>
> On Mon, Jan 19, 2015 at 1:55 AM, Tomas Krajca <tomas at repositpower.com> wrote:
>> Hi,
>>
>> I've reported this weird bug https://github.com/zeromq/libzmq/issues/1302
>> that we hit last week, I wonder if anybody experienced the same thing or can
>> reproduce it. Basically, we saw a progressive file handle leak that crashed
>> our application after about an hour of network outage.
>>
>> Any thoughts of which part of the code could the bug be in? We've got a C++
>> programmer in our team but don't know enough about libzmq internals to try
>> to fix this.
>>
>> Thanks,
>> Tomas