From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richie <listmail@triad.rr.com>
Subject: Re: [PATCH] xend: update init script to avoid grep on
	non-existent file system
Date: Sat, 15 May 2010 10:56:00 -0400
Message-ID: <4BEEB600.4090906@triad.rr.com>
References: <C8140D61.145AC%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>
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Sure. I agree much simpler, but is this blurb in the grep manpage a conce=
rn?
-s, --no-messages
Suppress error messages about nonexistent or unreadable files.
Portability note: unlike GNU grep, 7th Edition Unix grep did not
conform to POSIX, because it lacked -q and its -s option behaved
like GNU grep=92s -q option. USG-style grep also lacked -q but
its -s option behaved like GNU grep. *Portable shell scripts
should avoid both -q and -s and should redirect standard and
error output to /dev/null instead*. (-s is specified by POSIX.)

I'm not sure where all the xend daemon can run? is it always running on=20
linux, thus implying (modern?) GNU grep? The reason I am bringing this=20
up is that I recall having grep related issues when running git on=20
Solaris (without gnu utilities installed) for this very reason. I will=20
re-sumbit accordingly.


Keir Fraser wrote:
> On 15/05/2010 05:16, "Richie" <listmail@triad.rr.com> wrote:
>
>  =20
>> I'm seeing a grep error during bare metal pvops kernel boot.  In the
>> init script, the previous checks will avoid/perform the /proc/xen moun=
t
>> as appropriate, but then it does a grep on /proc/xen/capabilities
>> without ensuring that /proc/xen is actually mounted.  This is my attem=
pt
>> (read: first patch :) ) to avoid it.
>>    =20
>
> Richie,
>
> Can you try adding the -s option to grep instead (i.e., grep -qs)? Shou=
ld be
> a simpler way to achieve the same thing. I'll apply that instead if it =
works
> okay for you.
>
>  -- Keir
>
>
>  =20