Dear sir,

I have a lot of files in the server with name like checkfile.jsp and in the file has two or three lines with an ip address xxx.xxx.xxx in it. I wish to know if there any command to grep for the ip address and remove it
in file but keep the " ", eg "xxx.xxx.xxx"

man sed

Some suggestions for you: http://www.linuxquestions.org/questi...check.-219187/

What you need is take a Regex (Regular Expression) book and read it.

So you want to keep everything in the file but this particular IP address, yes? I detect the distinct aroma of homework. Here is a hint:

Sed command is to do within a single file only. I have hundreds of files which has this same ip inside. Can i use something like this find "xxx.xxx.xx" -exec rm {} \; ?

sed takes wildcards for file spec
http://www.grymoire.com/Unix/Sed.html

and you can do in-place editing
http://linux.die.net/man/1/sed

No. The find command finds files by their properties, not by their contents. You could use find to find the files by name and then sed to edit them.

I can't create an example right now, but:

1. Use "find" to create a list of target files.
2. Apply the list to a "sed" filter that reads the original file and places the result in a temp file.
3. Copy the temp file over the original.
4. Continue looping over file paths.

But don't try to sed from a particular file directly to the same file:

sed "regex" < file > file

This is a bad mistake. It sometimes works while you are testing, then when you turn your back, it starts eating files. Always use a temp file for the output of the pipe.

can i do like this :

grep "xxx.xxx.xxx" . > /tmp/ip.txt
for i in `cat /tmp/ip.txt`
do
sed -i -e 's/xxx.xxx.xxx/ /g' $i
done

The above will directly edit the actual file.
I am not sure how is 'not to sed from a particular file directly to the same file'

No.tells grep to search the current directory and will put nothing in /tmp/ip.txt. You could have tried it and found that.

If you omit the -i from the sed command then it will write its output to stdout and you can direct it to another file. Good idea while you are testing the method