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Date: Tue, 16 Feb 2010 21:17:22 +0800
From: =?utf-8?Q?Am=C3=A9rico?= Wang <xiyou.wangcong@gmail.com>
To: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Nikita V. Youshchenko" <yoush@cs.msu.su>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: Extended error reporting to user space?
Message-ID: <20100216131722.GA4382@hack.private>
References: <201002161520.26700@zigzag.lvk.cs.msu.su> <b6fcc0a1002160423o1269996bw34c033015b1ab500@mail.gmail.com>
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On Tue, Feb 16, 2010 at 02:23:55PM +0200, Alexey Dobriyan wrote:
>On Tue, Feb 16, 2010 at 2:20 PM, Nikita V. Youshchenko <yoush@cs.msu.su> wrote:
>> Unfortunately this -EINVAL is not really useful.
>
>There is no such thing.
>Driver can spit messages with printk() though.

Right, if errno is not enough, printk() is.

You could also use other interface to debug, but printk() is the
simplest.

Thanks.