CentOS - Oct 2009 - permission script

I just wrote a little script, that will echo a message to the user, if it
doesn't have enough permission:



$ if ! [ "$(env LC_MESSAGES=C ifconfig wlan0 down | grep -i denied)"
== "" ]; then echo "no permission"; fi

SIOCSIFFLAGS: Permission denied

$ sudo su

[sudo] password for USER: 

# if ! [ "$(env LC_MESSAGES=C ifconfig wlan0 down | grep -i denied)"
== "" ]; then echo "no permission"; fi

# 



but it won't works



why?




      
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The output message "Permission denied" comes from STDERR not from
STDIN.
You should redirect stderr to stdin on your command, to make it work.

ifconfig wlan0 down 2>&1 | grep -i denied


On Sun, Oct 25, 2009 at 2:42 PM, Eugeneapolinary Ju <
eugeneapolinary81 at yahoo.com> wrote:
>  I just wrote a little script, that will echo a message to the user, if it
> doesn't have enough permission:
>
> $ if ! [ "$(env LC_MESSAGES=C ifconfig wlan0 down | grep -i
denied)" == ""
> ]; then echo "no permission"; fi
> SIOCSIFFLAGS: Permission denied
> $ sudo su
> [sudo] password for USER:
> # if ! [ "$(env LC_MESSAGES=C ifconfig wlan0 down | grep -i
denied)" == ""
> ]; then echo "no permission"; fi
> #
>
> but it won't works
>
> why?
>
>
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
>
>
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