[ale] Get host's IP address as an unprivileged user?

[Geoffrey Myers]

Geoffrey Myers wrote:
> Derek Atkins wrote:
>> JD <jdp at algoloma.com> writes:
>>
>>> On 06/03/2011 09:25 AM, James Sumners wrote:
>>>> I need to get the IP address of the local machine on which a script is
>>>> being executed. The script is going to be run by an unprivileged user
>>>> (so /sbin is not in the PATH). Does anyone know of a better way than
>>>> this:
>>>>
>>>> IP=$(host $(hostname) | awk '{print $4}')
>>>>
>>> I never trust the PATH in scripts.  Anyone can call /sbin/ifconfig.
>>> If you must, just add :/sbin to your PATH (ew).
>> Like JD said, you do not need to be root to run ifconfig:.
>>
>> [warlord at dev webdav]$ whoami
>> warlord
>> [warlord at dev webdav]$ /sbin/ifconfig wlan0 
>> wlan0     Link encap:Ethernet  HWaddr 00:21:6A:90:98:58  
>>           inet addr:192.168.248.100  Bcast:192.168.248.255  Mask:255.255.255.0
>> ...
>> [warlord at dev webdav]$ /sbin/ifconfig wlan0 | grep 'inet addr' | tr : ' ' | awk '{print $3}'
>> 192.168.248.100
> 
> You probably can't guarantee that the device will be wlan0.  Further, 
> you can combine your grep, awk, and tr into a single awk script:
> 
> ifconfig| awk -F'[" ":]' '/Bcast/ {print  $16, NF}'
> 
> Note, I've looking for Bcast, should match any configured interfaces. 
> Problem is, if you have more then one interface configured....\

that should have been:

ifconfig| awk -F'[" ":]' '/Bcast/ {print  $16}'

I had the NF in the original output to see if I was counting the fields 
properly. :(

> 
> 
>> -derek
> 
> 


-- 
Until later, Geoffrey

"I predict future happiness for America if they can prevent
the government from wasting the labors of the people under
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