Re: [PATCH] xend: update init script to avoid grep on non-existent file system

[Richie <listmail@triad.rr.com>]

Sure. I agree much simpler, but is this blurb in the grep manpage a concern?
-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’s -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 
linux, thus implying (modern?) GNU grep? The reason I am bringing this 
up is that I recall having grep related issues when running git on 
Solaris (without gnu utilities installed) for this very reason. I will 
re-sumbit accordingly.


Keir Fraser wrote:
> On 15/05/2010 05:16, "Richie" <listmail@triad.rr.com> wrote:
>
>   
>> 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 mount
>> as appropriate, but then it does a grep on /proc/xen/capabilities
>> without ensuring that /proc/xen is actually mounted.  This is my attempt
>> (read: first patch :) ) to avoid it.
>>     
>
> Richie,
>
> Can you try adding the -s option to grep instead (i.e., grep -qs)? Should be
> a simpler way to achieve the same thing. I'll apply that instead if it works
> okay for you.
>
>  -- Keir
>
>
>