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Read just the IP address of a device

Terminal - Read just the IP address of a device
/sbin/ifconfig | awk -F'[ :]+' '/inet addr/{print $4}'
2009-07-21 14:18:17
User: inof
Functions: awk
-1
Read just the IP address of a device

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

/sbin/ifconfig -a | awk '/inet/{print $2}'

Alternatives

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 | grep inet | cut -f 2 -d ":" | cut -f 1 -d " "
2009-07-21 21:42:04
User: random_bob
Functions: cut grep
-1

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
-1

to clean up the extra lines

ip addr|grep "inet "
2009-07-22 07:38:06
User: RickDeckardt
Functions: grep
-3

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

running bash the /sbin/ifconfig -a | awk '/inet/{print $2}' worked fine with just a little extra output (1 extra line per nic),

Comment by random_bob 305 weeks and 2 days ago

@random_bob: Yeah, but when you need the IPs in a script, you must get rid of the extra output, so the simple solution isn't sufficient. Parsing usually needs to be exact in scripts.

Otherwise "ifconfig | grep inet" would work fine, too, with 'some' extra output ... :-)

Comment by inof 294 weeks and 2 days ago

Your point of view

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