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May 19, 2015 - A Look At The New Commandlinefu
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Filtering IP address from ifconfig usefule in scripts

Terminal - Filtering IP address from ifconfig usefule in scripts
IPADDR=`ifconfig eth0 | grep -i inet | awk -F: '{print $2}'| awk '{print $1}'`
2009-02-25 22:58:19
User: rockon
Functions: awk grep
Filtering IP address from ifconfig usefule in scripts

Useful in scripts while you just need an IP address in a variable.


There are 2 alternatives - vote for the best!

Terminal - Alternatives
/sbin/ifconfig eth0 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'
print ${$(ifconfig wlan0)[6]}
2013-03-23 20:29:29
User: khayyam
Functions: ifconfig
Tags: zsh

A method for aquiring the ip address using zsh. If you prefer the use of iproute2 (which, frankly, you should) then the following should provide the same (ip outputs CIDR addresses):

print ${$(ip -o -4 a s eth0)[4]}

we could also pass a qualifier to take only the IP and not the (CIDR) mask

print ${$(ip -o -4 a s eth0)[4]:h}

or, similarly, for the MAC address:

print ${$(ip l l eth0)[15]}

Know a better way?

If you can do better, submit your command here.

What others think

Or, using sed only :

ifconfig eth0 | sed -n "s/.*inet [^ ]*:\([^ ]*\) .*/\1/p"

and I'm sure it could be done using awk only if you prefer awk.

Comment by raphink 406 weeks and 1 day ago
ifconfig en1 | grep -E 'inet.[0-9]' | awk '{ print $2}'

Nice part is you could easily show all interfaces by simply 'infconfig | grep...'

And throw a | grep -v '' | to ignore loopbacks (or other nets you want to ignore)

ifconfig | grep -E 'inet.[0-9]' | grep -v '' | awk '{ print $2}'

* Not as cool looking as yours though and only tested on Mac :)

Comment by vaporub 406 weeks and 1 day ago

you can put the grep patterns inside the awk command

ifconfig en0 | awk '/inet.[0-9]/ {print $2}'

and if you wish to show all except

ifconfig | awk '/inet.[0-9]/&&!/ {print $2}'
Comment by NynjaWitay 406 weeks ago

you can put the grep patterns inside the awk command

ifconfig en0 | awk '/inet.[0-9]/ {print $2}'

and if you wish to show all except

ifconfig | awk '/inet.[0-9]/&&!/ {print $2}'
Comment by NynjaWitay 406 weeks ago

Your point of view

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