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pooppp · 05-28-2008, 02:28 AM

Hai,
I am having a txt file tht contains two fields such as name & IP address. I need to extract only tht IP address field. Give some idea.

indeliblestamp · 05-28-2008, 02:33 AM

A sample entry would be useful. Assuming its something like /etc/hosts, this should work fine:

Code:

cat filename | awk '{print $2}'

colucix · 05-28-2008, 02:36 AM

Some examples

Code:

IP=$(cut -f2 -d\  file)

note the escaped blank space specified as delimiter (cut considers TAB as default delimiter).

Code:

IP=$(awk '{print $2}' file)

if the file has multiple lines and you want to read the second field of each line on at a time, you can use a loop using read with two input variables

Code:

while read name ip
do
  echo $ip
done < file

chrism01 · 05-28-2008, 07:41 PM

Personally, instead of

IP=$(cut -f2 -d\ file)

I'd use

IP=$(cut -f2 -d' ' file)

I just dislike using backslash if I can do it 'nicer'

Of course, you may also see the backquote used

IP=`cut -f2 -d' ' file`

bit more old school and the brackets version nests better.