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From: "Linh Dang" <linhd@nortel.com>
To: linux-kernel@vger.kernel.org
Subject: Re: Environment variables inside the kernel?
Date: Thu, 18 Aug 2005 14:23:51 -0400	[thread overview]
Message-ID: <wn5slx75cjs.fsf@linhd-2.ca.nortel.com> (raw)
In-Reply-To: <m2ek8r5hhh.fsf@Douglas-McNaughts-Powerbook.local> (Douglas McNaught's message of "Thu, 18 Aug 2005 12:37:14 -0400")

Douglas McNaught <doug@mcnaught.org> wrote:

>
> If someone is insisting you use environment varaiables in kernel
> code, challenge them to show you where they are implemented in the
> kernel.  :)
>
> -Doug

They're in current process's vm. You just have to parse it yourself.

something along the (untested) lines:

        struct mm_struct *mm = current ? get_task_mm(current) : NULL;

        if (mm) {
                unsigned env_len = mm->env_end - mm->env_start;
                char* env = kmalloc(env_len, GFP_KERNEL);
                access_process_vm(current, mm->env_start, env,
                                           env_len, 0);

                /* env is now a big buffer containing null-terminated
                   strings representing evironment variables */

                mmput(mm);
        }

-- 
Linh Dang

  reply	other threads:[~2005-08-18 18:23 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-08-18 15:44 Environment variables inside the kernel? Guillermo López Alejos
2005-08-18 16:02 ` linux-os (Dick Johnson)
2005-08-18 16:03 ` jerome lacoste
2005-08-18 16:12 ` Ingo Oeser
2005-08-18 17:27   ` Christoph Lameter
2005-08-18 16:37 ` Douglas McNaught
2005-08-18 18:23   ` Linh Dang [this message]
2005-08-18 18:48     ` Guillermo López Alejos
2005-08-18 19:43       ` Emilio Jesús Gallego Arias
2005-08-21 22:12       ` Eric W. Biederman
2005-08-22  9:05         ` Guillermo López Alejos
2005-08-22  9:18           ` Eric W. Biederman
2005-08-25  8:59             ` Guillermo López Alejos
2005-08-22 20:38       ` Helge Hafting
2005-08-18 23:12     ` Alan Cox
2005-08-18 22:55       ` Peter M. Groen
2005-08-19 10:28         ` Guillermo López Alejos

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