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Read just the IP address of a device

Terminal - Read just the IP address of a device
ip addr|grep "inet "
2009-07-22 07:38:06
User: RickDeckardt
Functions: grep
Read just the IP address of a device

Shows a single line per interface (device), with its IPv4 settings.

Shorter command, better readability in output.


There are 4 alternatives - vote for the best!

Terminal - Alternatives
/sbin/ip -f inet addr | sed -rn 's/.*inet ([^ ]+).*(eth[[:digit:]]*(:[[:digit:]]+)?)/\2 \1/p' | column -t
ifconfig -l | xargs -n1 ipconfig getifaddr 2> /dev/null
/sbin/ifconfig | awk -F'[ :]+' '/inet addr/{print $4}'
2009-07-21 14:18:17
User: inof
Functions: awk

That one works on Linux. On BSD and Solaris, the ifconfig output is much easier to parse:

/sbin/ifconfig -a | awk '/inet/{print $2}'
/sbin/ifconfig | grep inet | cut -f 2 -d ":" | cut -f 1 -d " "
2009-07-21 21:42:04
User: random_bob
Functions: cut grep

another way to output the IP address' of the system

/sbin/ifconfig | grep inet | cut -f 2 -d ":" | cut -f 1 -d " " |egrep -v "^$"
2009-07-22 07:27:54
User: giray
Functions: cut egrep grep

to clean up the extra lines

Know a better way?

If you can do better, submit your command here.

What others think

Read man of ip command !!!

ip -f inet addr

Comment by Playload 378 weeks and 5 days ago

All of these assume you have one interface which is basically never true these days :-)

it's worth installing "moreutils" to get

ifdata -pa wlan0

which gives just the dotted-quad, no further parsing needed (unlike the "ip" example)

Comment by eichin 378 weeks and 4 days ago

First will be eth0 , then eth1 if , then localhost

ifconfig | grep -i "inet addr"

inet addr: Bcast: Mask:

inet addr: Mask:

Comment by hemanth 378 weeks and 4 days ago

it's not too difficult to add an "eth#" after the ifconfig

Comment by random_bob 375 weeks and 5 days ago

Your point of view

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