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DᴀʀᴛʜVᴀᴅᴇʀ
Asked: 2013-11-19 10:23:03 +0800 CST

Code works in terminal but not in script for renaming (manipulate filenames with spaces)

  • 772

I want to learn more so I have tried to script more than just using the terminal. I know rename and I can rename image files with rename 's/ /_/g' *.jpg but when I write it in a shell script to point at a directory:

DIRECTORY="/foo/bar"

for imgfile in $(find $DIRECTORY -type f -name \*.jpg); do
    echo 'replacing whitespace in' $(basename $imgfile)
    rename -f 's/ /_/g' *.jpg 
done

it doesn't work and the terminal will take a file (example: 1234 abcd.jpg) and echo abcd.jpg. So where am I going wrong?

command-line

2 Answers

  1. Best Answer

    Spaces in filenames are evil.

    I see three problems with the script:

    1. when doing the for... loop, you will have two different values when you find a file with space. i.e., if you have the files "file1 1.jpg" and "file2 2.jpg" and you do:

      for i in $(find . -type f -name \*.jpg); do 
   echo $i
done

      You'll have 

      ./file1 
1.jpg
./file2
2.jpg

      because the shell breaks the argument at spaces. The output of the $(find ...) command will be 

      ./file1 1.jpg 
./file2 2.jpg

      Which are four words for the command for to be assigned at $i --- by default the shell treats spaces and newlines in the same way when expanding.

      You can circumvent this changing the IFS char.

      Your first line could look like:

      IFS=$'\n' find $DIRECTORY -type f -name \*.jpg | while read -r imgfile; do

    2. you are feeding the for loop with a single file name, so you should say: 

      rename -f 's/ /_/g' "$imgfile"

      otherwise *.jpg is expanded in the current directory, and not in $DIRECTORY (and note the quotes --- given that $imgfile is going to have spaces in it).

    3. even then, if $DIRECTORY has some path component with spaces in it, the rename will fail (there will be intermediate directories that do not exist).

    4. suggestion (keeping it simple):

      DIRECTORY="/foo/bar"
cd $DIRECTORY
rename -f 's/ /_/g' *.jpg

      doesn't do what you want?

    Added: my script (created ages ago, when there was no rename in Unix), is this --- it will remove spaces and tab in all files in current dir that have them in the name: 

    # 
ls -1  | grep -E " |\t" | while read i; do
    a=`echo $i | tr " \t" "__"`
    mv -v "$i" $a
done

    Added++: this link I found researching this answer is excellent.

    • 5

  2. Best way to parse the result from find is by null terminate the output with -print0

    #!/bin/bash

while IFS= read -d '' -r; do
    rename -f "s/ /_/g" "$REPLY"
    if [[ ! -f $REPLY ]]; then
        echo "Renaming file: $(basename "$REPLY")"
    fi
done < <(find -type f -name '*.jpg' -print0)

    (You can manage without a loop).

    $ find -type f -name '*.jpg' \
    -exec bash -c 'rename -f "s/ /_/g" "$1"; \
    [[ -f $1 ]] || echo "Renaming file: $(basename "$1")"' _ '{}' \;
    • 0