Mailing-List: contact modules-dev-help@httpd.apache.org; run by ezmlm
Precedence: bulk
Reply-To: modules-dev@httpd.apache.org
Received-SPF: pass (nike.apache.org: local policy)
Message-ID: <4F54966C.4020005@unipr.it>
Date: Mon, 05 Mar 2012 11:33:16 +0100
From: Massimo Manghi <massimo.manghi@unipr.it>
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US;
 rv:1.9.2.24) Gecko/20111114 Icedove/3.1.16
MIME-Version: 1.0
To: modules-dev@httpd.apache.org
Subject: Re: thread ID
References: <993_1330619359_4F4FA3DF_993_1203_1_4F4FA3DE.2040900@orange.com>
 <CAHQurc_FroEPfEZfYk518kbdpY6jajwdDUQCeUdN9HhFfHKL0g@mail.gmail.com>
 <4F500785.50707@gmail.com> <4F525D23.3020803@kippdata.de>
In-Reply-To: <4F525D23.3020803@kippdata.de>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

On 03/03/2012 07:04 PM, Rainer Jung wrote:
> On 02.03.2012 00:34, Sorin Manolache wrote:
>> On 03/02/12 00:21, Ben Noordhuis wrote:
>>> On Thu, Mar 1, 2012 at 17:29,<sorin.manolache@orange.com> wrote:
>>>> Hello,
>>>>
>>>> I would need a memory buffer associated per worker thread (in the 
>>>> worker
>>>> MPM) or to each process (in the prefork MPM).
>>>>
>>>> In order to do that, I would need a map thread<->buffer. So, I would
>>>> need a sort of thread ID/key/handle that stays the same during the
>>>> lifetime of the thread and no two threads in the same process can have
>>>> the same ID/key/handle.
>>>>
>>>> What is the most portable way to get this thread ID?
>>>>
>>>> I thought of r->connection->id. It works but it is not very 
>>>> portable as
>>>> it is not guaranteed that two connections created by the same thread
>>>> will have the same id. They do for now.
>>>>
>>>> If r->connection->sbh was not opaque it would be great, because
>>>> sbh->thread_num would be exactly what I need.
>>>>
>>>> I could also use pthread_self. It works too but, in general, it is not
>>>> guaranteed that the worker threads are pthreads.
>>>>
>>>>
>>>> Thank you for your help.
>>>>
>>>> Sorin
>>>
>>> What about apr_os_thread_current()? It returns a opaque value that's a
>>> pthread_t on Unices and a pseudo-HANDLE on Windows. Read this[1] to
>>> understand what that means.
>>>
>>> As a recovering standards lawyer I should probably point out that
>>> pthread_t is an opaque type that's not guaranteed to be convertible to
>>> a numeric value (or to anything, really). That said, I've never seen a
>>> pthreads implementation where that wasn't the case.
>>>
>>> [1]
>>> http://msdn.microsoft.com/en-us/library/windows/desktop/ms683182%28v=vs.85%29.aspx 
>>>
>>>
>>
>> Thank you, it's what I need.
>
> You might also want to check the function log_tid() in server/log.c of 
> httpd's trunk or 2.4. The thread id gets logged in the error log by 
> default since 2.4, so that code converts it to a number.
>
> Regards,
>
> Rainer

true, the ID is logged now, but is the function handling the thread id 
public?

  -- Massimo