LinuxQuestions.org - [SOLVED] Would you recommend sed to .....

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Would you recommend sed to .....

I have a document.
I want to replace all the c's and C's in it with %1
all the f's and F's in it with %2

i can get sed to do one of them but for some reason i can't get the script to do all the conversions at once.

Have you tried:

Code:

sed -e <pattern1> -e <pattern2> -e . . .

My bet is that you're missing a "g" at the end of your substitution commands. e.g.

Code:

$ echo 'abcdefghABCDEFGH' | sed 's/[fF]/%2/g 

> s/[cC]/%1/g'

ab%1de%2ghAB%1DE%2GH

Without 'g', s/// only replaces the first instance of the search pattern that it finds in each line.

edit: oops, I missed Dark Helmet's post. He's right, maybe the problem is confusion about how to do multiple sed commands at once. The multiple -e options is a cleaner way to do it than the literal newline that I used.

Code:

#!/bin/bash

#

#

for fl in *.txt; do

mv $fl $fl.old

sed -e 's/d/%2/' -e 's/a/%1/' -e 's/e/%3/' $fl.old > $fl

done

cause i want to do all the txt files in that directory and make a backup.
but that seemed to do the trick the -e option. i want to be able to select the file i want to do this too so more reading for me .;'

thanks peeps.

Quote:

Originally Posted by ieatbunnies (Post 4157990)

Code:

#!/bin/bash

#

#

for fl in *.txt; do

mv $fl $fl.old

sed -e 's/d/%2/' -e 's/a/%1/' -e 's/e/%3/' $fl.old > $fl

done

Hi,

You do not need a loop. sed can do this:

Code:

sed -i.old 's/[cC]/%1/g;s/[fF]/%2/g' *.txt

[EDIT]
Just read that you want to select the file, so you do need a loop for your purpose. But you do not need to manually make a backup first. The -i option in sed will create a backup of the file if you give it an extension, e.g. -i.old will create a backup file with extension '*.old ' and before editing the file.