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Get all IPs via ifconfig

Terminal - Get all IPs via ifconfig
ifconfig | perl -nle'/dr:(\S+)/ && print $1'
2009-07-23 09:33:31
User: xsawyerx
Functions: ifconfig perl
11
Get all IPs via ifconfig

Fetches the IPs and ONLY the IPs from ifconfig. Simplest, shortest, cleanest.

Perl is too good to be true...

(P.S.: credit should go to Peteris Krumins at catonmat.net)

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
ifconfig -a | perl -nle'/(\d+\.\d+\.\d+\.\d+)/ && print $1'
2009-07-31 09:49:17
User: sneaker
Functions: ifconfig perl
12

works on Linux and Solaris. I think it will work on nearly all *nix-es

ifconfig | awk -F':| +' '/ddr:/{print $4}'
2009-07-25 22:51:08
User: 0x89
Functions: awk ifconfig
Tags: Linux ifconfig
1

and, a lot uglier, with sed:

ifconfig | sed -n '/inet addr:/s/[^:]\+:\(\S\+\).*/\1/p'

Edit:

Wanted to be shorter than the perl version. Still think that the perl version is the best..

ifconfig | awk '/ddr:[0-9]/ {sub(/addr:/, ""); print $2}'
2009-07-31 09:30:54
User: danny_b85
Functions: awk ifconfig
Tags: Linux ifconfig
1

The initial version of this command also outputted extra empty lines, so it went like this:

192.168.166.48

127.0.0.1

This happened on Ubuntu, i haven't tested on anything else.

ifconfig | awk '/inet / {sub(/addr:/, "", $2); print $2}'
ipconfig getpacket en0 | grep yi| sed s."yiaddr = "."en0: ". ipconfig getpacket en1 | grep yi| sed s."yiaddr = "."en1: ".

Know a better way?

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What others think

Perl++!

Comment by linuxrawkstar 304 weeks and 2 days ago

Great, I'll be using this. Thanks.

One question, know a way to have this pull just a specific interface's IP from ifconfig?

Comment by fritz_monroe 304 weeks and 1 day ago

Won't work on non-Linux Unices. Modded down.

Comment by artis 304 weeks and 1 day ago
ifconfig | grep "inet addr" | cut -d: -f2 | cut -d' ' -f1
Comment by trungtm 304 weeks and 1 day ago

Your point of view

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