Mailing-List: contact users-help@httpd.apache.org; run by ezmlm
Precedence: bulk
Reply-To: users@httpd.apache.org
Received-SPF: neutral (nike.apache.org: local policy)
In-Reply-To: <4A88A8C6.6080903@bigpond.com>
References: <4A88A8C6.6080903@bigpond.com>
Mime-Version: 1.0 (Apple Message framework v753.1)
Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
Message-Id: <A0F58442-FD07-4133-B0A2-C4555609FE5F@webthing.com>
Cc: users@httpd.apache.org
Content-Transfer-Encoding: 7bit
From: Nick Kew <nick@webthing.com>
Date: Fri, 21 Aug 2009 05:22:24 +0100
To: APR Developer List <dev@apr.apache.org>
Subject: Re: [users@httpd] DBDPersist Off in vhost causes startup error log
 entries

A post on users@httpd highlights inconsistent practice in apr.

On 17 Aug 2009, at 01:48, Peter Horn wrote:

> Hi All,
> I've been running Apache 2.2.9 / PHP 5.2.6 / Win XP SP3 with 3  
> named vhosts for about a year with no real problems. Recently I  
> added a fourth vhost to run a Drupal site. This involved adding  
> mySQL, and it all worked after the usual few setup iterations.  
> After the site was running happily for a couple of weeks, I  
> revisited the setup and removed 'DBDPersist Off' from the vhost.  
> After I did this, I get the following messages in the error log at  
> startup, even though the site subsequently appears to work  
> correctly and there are no 'runtime' errors:
>
> [Sat Aug 15 12:25:22 2009] [error] (OS 126)The specified module  
> could not be found.  : DBD: mod_dbd not compatible with APR in  
> get_driver
> [Sat Aug 15 12:25:22 2009] [error] (OS 126)The specified module  
> could not be found.  : DBD: failed to initialise

Problem: The user has got a confusing error message.

Diagnosis: apr_dso_load and apr_dso_sym on Windows platform
return an OS error instead of an APR error on failure.

As an APR user, mod_dbd handles the APR errors APR_EDSOOPEN
and APR_ESYMNOTFOUND and gives the user a tailored error
message.  That was based on the behaviour of unix/apr_dso.

It's an inconsistency, and IMHO it's the Windows that should
be fixed.  APR is supposed to shield applications from this
kind of platform-specific detail.

Quick survey of other APR platforms:
aix, beos, netware, os390 - conform to UNIX behaviour.
os2 - uses APR_FROM_OS_ERROR

So the safest/most consistent thing would seem to be to
fixup both Windows and OS2.  Thoughts?

-- 
Nick Kew

---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
   "   from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org