[SOLVED] Rename series of files with 2 extentions by help of sed

Issue

I have tried to rename some files which has 2 extensions in a folder which also has multiple folders. For example :

"./3/test/us.bak.alt" 
 "./3/test/ca.bak.alt" 
 "./3/test/me.bak.alt" 
 "./3/test/mi.bak.alt"
 "./3/new.BAK.alt" 
 "./3/alt.bak.alt"

These should be renamed to *.BAK (so the .alt at the end should be deleted), but only if the .BAK file does not already exist. And I tried this code :

 find  -name "*.alt" | sed 's/\(.*\)\.alt/mv "&" \1.BAK"/'

the oupt should be like this:

     "./3/test/us.BAK" 
     "./3/test/ca.BAK" 
     "./3/test/me.BAK" 
     "./3/test/mi.BAK"
     "./3/new.BAK"
     "./3/alt.BAK"

What I'm missing here?

Solution

You are missing several things:

1. You should limit the find search to files.
2. Your sed script does not replace .bak.alt by .BAK, it replaces .alt by .BAK.
3. There is a missing double quote in your sed script.
4. You should limit the sed search to the end of the file names.
5. You have a new.BAK.alt file in your input list.
6. You have an empty string "" in your input list.
7. You have a ./3/test/us.bak.alt in your desired output list, which apparently contradicts your specification.

Let's ignore the 3 last issues, they are probably typos. To fix the 4 others try:

find . -type f -name "*.bak.alt" | sed 's/\(.*\)\.bak\.alt$/mv "&" "\1.BAK"/'

If the fifth issue is a real one and you also have *.BAK.alt files that you want to rename as *.BAK:

find . -type f \( -name "*.bak.alt" -o -name "*.BAK.alt" \) |
  sed -E 's/(.*)\.(bak|BAK)\.alt$/mv "&" "\1.BAK"/'

With one or the other, when you will be satisfied with the printed output, you can execute them all with a very small change if you use GNU sed:

find . -type f -name "*.bak.alt" | sed 's/\(.*\)\.bak\.alt$/mv "&" "\1.BAK"/;e'

or:

find . -type f \( -name "*.bak.alt" -o -name "*.BAK.alt" \) |
  sed -E 's/(.*)\.(bak|BAK)\.alt$/mv "&" "\1.BAK"/;e'

(the e sed command executes the content of the pattern space).

Answered By - Renaud Pacalet

Answer Checked By - Robin (WPSolving Admin)