Shell Programming and Scripting

Hi,

Can some one guide me to identify the position of a character using index in UNIX.

I have a record like "17/11/2010 15:16:39;reject;10.44.48.65;daemon alert; src: 10.44.48.112; dst: 172.21.52.88" . I need to identify the value which comes after _src:_ (_ denotes space).

I am able to identify the no. of characters till _src:_ as below:

s1="17/11/2010 15:16:39;reject;10.44.48.65;daemon alert src: 10.44.48.112; dst: 172.21.52.88"

s2=" src: "

start_val=`awk -v a="$s1" -v b="$s2" 'BEGIN{print index(a,b)+6}'`

But am not able to identify the character position of ";" which comes after _src:_ .

If I can identify that character position then I can pick the value using substr.

Can some one help me to identify the position.

Also If any one is having better approach please guide me.


Many Thanks in advance.
MSK

Are u looking to extract an IP address comes after _src:_ ?? If its is so then

Code:

echo "17/11/2010 15:16:39;reject;10.44.48.65;daemon alert; src: 10.44.48.112; dst: 172.21.52.88" | sed 's/.*; src: (.*); /$1/g'

output

10.44.48.112

and if u r having this data stored in file then

Code:

sed 's/.*; src: (.*); /$1/g' filename

Thanks for your reply R0H0N.

But it is returning the value as my input.

Make the changes in sed command for finding an exact string as per your requirement. Or, delimit the special characters in sed command.

Hi R0H0N,

I executed the below command
echo "17/11/2010 15:16:39;reject;10.44.48.65;daemon alert; src: 10.44.48.112; dst: 172.21.52.88" | sed 's/.*; src: (.*); /$1/g'

but it is returning 17/11/2010 15:16:39;reject;10.44.48.65;daemon alert; src: 10.44.48.112; dst: 172.21.52.88

But am expecting the 10.44.48.112.

Many Thanks

Code:

sed -n 's/.*; src: \(.*\); /$1/g'

or

sed -n 's/.*; src: \(.*\); /\1/g'

try this

Code:

echo "17/11/2010 15:16:39;reject;10.44.48.65;daemon alert; src: 10.44.48.112; dst: 172.21.52.88" | sed 's/.*\(src: \)\(.*\);..*/\2/' -