How can I process a list of files that includes spaces in its names in Unix?

Question

I'm trying to list the files in a directory and do something to them in the Mac OS X prompt.

It should go like this: for f in $(ls -1); do echo $f; done

If I have files without spaces in their names (fileA.txt, fileB.txt), the echo works fine. If the files include spaces in their names ("file A.txt", "file B.txt"), I get 4 strings (file, A.txt, file, B.txt).

I've tried quoting the listing command, but it only changed the problem.

If I do this: for f in $(ls -1); do echo $f; done I get: file A.txt\nfile B.txt

(It displays correctly, but it is a single string and I need the 2 lines separated.

Answer 1

for f in *; do echo "$f"; done

should do what you want. Why are you using ls instead of * ?

In general, dealing with spaces in shell is a PITA. Take a look at the $IFS variable, or better yet at Perl, Ruby, Python, etc.

Answer 2

Check out the manpage for xargs:

it works like this:

ls -1 /tmp/*.jpeg | xargs rm

Answer 3

Here's an answer using $IFS as discussed by derobert http://www.cyberciti.biz/tips/handling-filenames-with-spaces-in-bash.html

Answer 4

Step away from ls if at all possible. Use find from the findutils package.

find /target/path -type f -print0 | xargs -0 your_command_here

-print0 will cause find to output the names separated by NUL characters (ASCII zero). The -0 argument to xargs tells it to expect the arguments separated by NUL characters too, so everything will work just fine.

Replace /target/path with the path under which your files are located.

-type f will only locate files. Use -type d for directories, or omit altogether to get both.

Replace your_command_here with the command you'll use to process the file names. (Note: If you run this from a shell using echo for your_command_here you'll get everything on one line - don't get confused by that shell artifact, xargs will do the expected right thing anyway.)

Edit: Alternatively (or if you don't have xargs), you can use the much less efficient

find /target/path -type f -exec your_command_here \{\} \;

\{\} \; is the escape for {} ; which is the placeholder for the currently processed file. find will then invoke your_command_here with {} ; replaced by the file name, and since your_command_here will be launched by find and not by the shell the spaces won't matter.

The second version will be less efficient since find will launch a new process for each and every file found. xargs is smart enough to pipe the commands to a newly launched process if it can figure it's safe to do so. Prefer the xargs version if you have the choice.

Answer 5

You can pipe the arguments into read. For example, to cat all files in the directory:

ls -1 | while read FILENAME; do cat "$FILENAME"; done

This means you can still use ls, as you have in your question, or any other command that produces $IFS delimited output.

The while loop makes it much easier to do several things to the argument, and makes complex processing more readable in my opinion. A contrived example:

ls -1 | while read FILE
do
    echo 1: "$FILE"
    echo 2: "$FILE"
done

Answer 6

look --quoting-style option. for instance, --quoting-style=c would produce :

$ ls --quoting-style=c

"file1" "file2" "dir one"