From mboxrd@z Thu Jan  1 00:00:00 1970
From: Josh Durgin <josh.durgin@inktank.com>
Subject: Re: [rados] Asynchronous operations
Date: Mon, 23 Jul 2012 09:07:20 -0700
Message-ID: <500D76B8.1070705@inktank.com>
References: <jsecti$m2u$1@dough.gmane.org> <Pine.LNX.4.64.1206270821040.18530@cobra.newdream.net> <jujscq$sug$1@dough.gmane.org>
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To: Rutger ter Borg <rutger@terborg.net>
Cc: ceph-devel@vger.kernel.org

On 07/23/2012 08:59 AM, Rutger ter Borg wrote:
> On 06/27/2012 05:22 PM, Sage Weil wrote:
>>
>> There is a get_return_value() method on the AioCompletion that gives you
>> bytes read (for reads).  For write operations, it is always 0
>> (success) or
>> an error code.
>>
>
> Thanks for the info. Maybe a bit of a newbie question, but in that case,
> how do I detect a read error, given an AioCompletion object?

It's the same as with writes - if there's an error, get_return_value
will give you the negative error code (i.e. -ENOENT, -EPERM, etc).