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From: Andreas Schwab <schwab@suse.de>
To: Jean Delvare <khali@linux-fr.org>
Cc: Greg KH <gregkh@suse.de>, Tejun Heo <htejun@gmail.com>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: sysfs root link count broken in 2.6.22-git5
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X-Yow: Yow!  Am I having fun yet?
Date: Wed, 18 Jul 2007 22:12:52 +0200
In-Reply-To: <20070718220652.15ad2c4b@hyperion.delvare> (Jean Delvare's
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Jean Delvare <khali@linux-fr.org> writes:

> On Tue, 17 Jul 2007 20:38:28 -0700, Greg KH wrote:
>>                                            Isn't there some glibc
>> function that can detect the mount point of a filesystem or directory?
>> Something in glibc parses /proc/mounts for something, I can't remember
>> what it is right now though, sorry.
>
> Maybe getmntent(3)? Sure I could use this, but how expensive compared
> to a single stat(2).

How about comparing the device numbers of /sys and its parent?  If they
are different then /sys is a mount point.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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"And now for something completely different."