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Get IPv4 of eth0 for use with scripts

Terminal - Get IPv4 of eth0 for use with scripts
ifconfig eth0 | grep 'inet addr' | cut -d ':' -f 2 | cut -d ' ' -f 1
2010-06-26 22:36:21
User: atoponce
Functions: cut grep ifconfig
2
Get IPv4 of eth0 for use with scripts

Simple and easy. No regex, no search and replace. Just clean, built-in tools.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
ifconfig eth0 | grep "inet " | cut -d ':' -f2 | awk '{print $1}'
2010-06-29 00:06:08
User: jaimerosario
Functions: awk cut grep ifconfig
3

I've been using it in a script to build from scratch proxy servers.

ip addr show eth0 | awk '/inet / {FS = "/"; $0 = $2; print $1}'
2010-06-30 14:33:48
User: kniht
Functions: awk
1

Combines wgzhao's grep | awk | sed into one awk command.

/sbin/ifconfig eth0 | grep 'inet addr:' | awk {'print $2'} | sed 's/addr://'
ifconfig eth0 | perl -ne "print if m/inet addr:((\d+\.){3})+/" | sed "s/inet addr//" | sed "s/Bcast//" |awk -F: '{print $2}'
2010-06-26 12:07:15
User: aceiro
Functions: awk ifconfig perl sed
0

only output the ip addres. I put double pipe with sed because not parse with operator OR (|) in redex.

ip addr show eth0 |grep 'inet\b' |awk '{print $2}' |sed -r -e 's/\/.*?//g'

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