Using sed in a shell script
 

In one of my last threads I asked a question about modifying a file, by removing everything in a line up to a certain word. Well what I got back was something similar to this :%s/^.*foo\ // What I need to know is how can I ad that to a script using sed? I have tried sed -n -e '%s/^.*foo\ //' file > newfile, however I keep getting an error "sed: -e expression #1, char 1: unknown command: '%', so is it not recognizing the '%'? and if not what should I use? Oh..and the script is not pearl.

Hi,

You don't need the % (no range is needed when you want to check the complete input file), if this is the complete sed statement, you also don't need the -e part. -e is used to string sed statements together. Which leaves you with this:

sed -n 's/^.*foo\ //' file > newfile

If you start working with variables inside the sed statement, you should use double quotes (") instead of singe (').

Hope this helps.

thanks druuna for sed question help!
 

You state that I don't need the -e but should use the -n. So what is the format I should use if I wanted to string sed statement? Say if I wanted to delete from the word foo to the end of the line? (opposite of my first question) :) example: 's/\foo*.*$//' how would I put the two together? what kind of seperator do I need to seperate the two commands or do I need a seperator at all? Thanks in advance!

Hi,

Nope, you decided to use the -n soption. I did tell you not to use the -e option.

Here's an example:
sed -e 's/foo/bar/g' -e '$d' -e '1,5s/this/that/' infile
The above changes every foo to bar, deletes the last line and changes the first this in a line to that if it is found in the first 5 lines of the inputfiile.

'Just' string them together with the -e option as shown in the example.

Hope this clears things up a bit.

Hi,
 

Thanks that does help very much!