Shell Programming and Scripting

Can anyone give me some examples of how I can parse the following lines of text so that all characters up to and including the @ symbol are deleted? Also, any duplicates would need to be deleted in order to produce the desired output. Any help is much appreciated and explanations of any solutions would be great too.


Dec 25 12:00:01 host1a pop3d: LOGIN: DEBUG: ip=[::ffff:192.168.1.1], username=someuser@domain1.com
Dec 25 12:00:01 host1a pop3d: LOGIN: DEBUG: ip=[::ffff:192.168.1.1], username=someuser@domain2.com
Dec 25 12:00:01 host1a pop3d: LOGIN: DEBUG: ip=[::ffff:192.168.1.1], username=someuser@domain1.com


Desired Output:
domain1.com
domain2.com

in bash

Code:

IFS="@"
sort -u file | while read line
do
    set -- $line
    echo $2
done

in awk:

Code:

# awk -F"@" '{print $2|"sort -u"}' file
# awk -F"@" '{array[$2]}END{for ( i in array ) print i}' file

Code:

awk -F@ '!a[$NF]++ {print $NF}' file

Using sed:

sed -e 's/^.*@//g' logfile | sort -u

Thanks guys! Thats very helpful, now can anyone tell me how I would use sed or awk to remove lines that contain a given string of text? Say for example, any lines containing the word "hello", also deleting any duplicate lines (ignoring case).

Bob
hello my name is bob
bob is my name
hello world
bob Hello
hello bob
bob
bob

output:
Bob
bob is my name

It's worth starting a new thread - pls do so in the future.
nawk -f jj.awk myFile

jj.awk:

Code:

{ str=tolower($0)}
str !~ "hello" && !(str in dups) { print; dups[str] }