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Read just the IP address of a device

Terminal - Read just the IP address of a device
/sbin/ifconfig | grep inet | cut -f 2 -d ":" | cut -f 1 -d " "
2009-07-21 21:42:04
User: random_bob
Functions: cut grep
Read just the IP address of a device

another way to output the IP address' of the system


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

to clean up the extra lines

ip addr|grep "inet "
2009-07-22 07:38:06
User: RickDeckardt
Functions: grep

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

Shorter command, better readability in output.

Know a better way?

If you can do better, submit your command here.

What others think

the "IP address of a device" is a misconception. A device may have several interfaces with several address each. ?What is the "IP of the device" in this case? The better candidate is the inteface used to get the local gateway, but it may be several gateways too...

Comment by prayer 331 weeks and 4 days ago

I've never worked with a multi-port NIC myself, but always assumed they'd have separate /dev entries for each port. is this not true?

Comment by random_bob 328 weeks and 5 days ago

Your point of view

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