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Old 01-07-2008, 01:13 PM   #1
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SED: edit ip address

Hi, I'm trying to figure out how to use sed to modify a returned ip address from the command:

ifconfig eth1 | grep 'inet addr' | awk '{print $2}' | sed -e 's/.*://'

When run, this returns

I need help to rewrite this to return the network address in the form of:

Any help would greatly be appreciated.


Old 01-07-2008, 01:30 PM   #2
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If it spits out "" and you need "" you could just append a piped "sed 's/1$/0/'
Old 01-07-2008, 02:58 PM   #3
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First, why is it returning the wrong address?

Second, do you need to change any digit in the last position to zero? (or just "1" to "0")
Old 01-07-2008, 05:00 PM   #4
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Originally Posted by n1wil View Post
ifconfig eth1 | grep 'inet addr' | awk '{print $2}' | sed -e 's/.*://'

# ifconfig eth0 | grep 'inet addr' | awk '{print $2}' | sed -e 's/\([a-z]\+[:]\)// | sed -e 's/\([0-9]\+\)\.\([0-9]\+\)\.\([0-9]\+\)\.\([0-9]\+\)/\1\.\2\.\3\.0/'
The first sed script will remove the "inet addr:" and the second one will replace the last octet with 0.
Old 01-08-2008, 03:18 PM   #5
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Could you please be more specific as to what output you are getting and what you would like to modify it to?


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