Rename files based on their parent directory using find/xargs command?

Question

I have a directory structure like this:

Project/
  |
  +--Part1/
  |    |
  |    +--audio.mp3
  |
  +--Part2/
  |    |
  |    +--audio.mp3
  |
  +--Part3/
  |    |
  |    +--audio.mp3
...

I want to end up with files called Part1.mp3, Part2.mp3, etc.

Each folder only contains a single file so there is no risk of clobbering files or dealing with multiple files with the same name.

I feel like I could do this with some sort of find/xargs command coupled with cut and mv but I can't figure out how to actually form the command.

Answer 1

These examples work in any POSIX shell and require no external programs.

This stores the Part*.mp3 files at the same level as the Project directory:

(cd Project && for i in Part*/audio.mp3; do echo mv "$i" ../"${i%/*}".mp3; done)

This keeps the Part*.mp3 files in the Project directory:

for i in Project/Part*/audio.mp3; do echo mv "$i" ./"${i%/*}".mp3; done

These solutions use the shell's pattern matching parameter expansion to produce the new filename.

 ${parameter%word}     Remove Smallest Suffix Pattern.  The word is expanded
                       to produce a pattern.  The parameter expansion then
                       results in parameter, with the smallest portion of
                       the suffix matched by the pattern deleted.

Answer 2

If you have the perl rename (sometimes called prename) you can do this:

( cd Project && rename 's!(.+)/(.+)(\.mp3)!$1.$3!' */audio.mp3 )

This takes each filename matching the shell glob */audio.mp3 and splits it into the directory, filename, and extension components. It then discards the filename part and renames the file.

Use rename -n ... to see what would happen, or use -v instead of -n to watch it happening as it runs.

Answer 3

pax -rwls'|.*/\(.*\)/audio\(\.mp3\)$|\1\2|p' \
    -s'|.*||' /path/to/Project .

That will use the POSIX pax command-line archiver utility to make hardlinks in the current directory named like parent_dirs_base.mp3 for every audio.mp3 found rooted in the tree at /path/to/Project. While doing so it will print any filename modifications it makes to stderr.

Use -k to prevent it possibly overwriting existing files with identical names as its link targets, or, and better yet, first change to an empty directory before running it.

In my opinion, there is a significant advantage to hardlinking first rather than directly mving the files you seek to work with: and that is that you get the chance to verify that the results you expect are the same as those you get before removing originals. When you have checked you can:

find /path/to/Project -name audio.mp3 -exec rm {} +

...to clean up and cut the file links down by one.

Answer 4

You can try something like this:

These are your files:

$ cd Project
$ find . -type f
./Part2/audio.mp3
./Part3/audio.mp3
./Part1/audio.mp3

Using dirname will return the name of their directory (assuming you only have one level of sub-directories). Thus:

$ find . -type f \
   | while read i ; do \
       d=$(dirname $i); echo renaming "$i" to "$d.mp3" ; \
     done
renaming ./Part2/audio.mp3 to ./Part2.mp3
renaming ./Part3/audio.mp3 to ./Part3.mp3
renaming ./Part1/audio.mp3 to ./Part1.mp3

And this will rename them:

$ find . -type f | while read i ; do d=$(dirname $i); mv "$i" "$d.mp3" ; done

Answer 5

Bash with perl style

for file in `find . -type f -name "*.mp3"`;
    do
        dir=$(dirname $file);
        bdir=$(basename $dir);
        bname=$(basename $file);
        new=$bdir.$bname;
        newname=${new//\.\./};
        newname_with_path=$dir/$newname
        if [ "$file" != "$newname_with_path" ]
        then
            echo mv -u $file  $newname_with_path ;
        fi
    done


    # replace 2 dots with nothing
    # bash 4.1.2 centos 6.4 no problem with or without bashslash
    newname=${new//../};