find command and file names with whitespace

sir_woland · 10-04-2007, 02:41 PM

Hi everyone,

I'm looking for a way to iterate through a list of files that have blank spaces in their names. I haven't had much luck with the find command so far:

Code:

for i in `find . -iname "*.mp3"`
do
  echo $i
done

since it splits the filenames by whitespaces. I found a successful workaround which involves renaming the files by replacing spaces with underscores, then reverting the operation, but this is far from elegant. Could someone provide a better solution?

David the H. · 10-04-2007, 03:27 PM

Try putting a pair of quotes around the whole find command, and another around the output variable, to contain the whole expression:

Code:

for i in "`find . -iname "*.mp3"`";
do echo "$i";
done

Arwkin · 10-04-2007, 03:30 PM

Using your example of echo, this will do what you want.

Code:

find . -iname "*.mp3" -exec echo \"{}\" \;

//edit - You probably want to use David's solution. With my solution, I had something like this in mind:

Code:

find . -iname "*.mp3" -exec mp3toogg -c \"{}\" output_dir \;

sir_woland · 10-04-2007, 04:22 PM

Thank you both -- unfortunately neither solution was quite what I'm looking for.

Trying the quoting trick gives me one long string with all the file names separated with line breaks, which echoes to the console quite nicely but still does not iterate correctly -- it goes through the for loop exactly once, regardless of the amount of files found. For X matches in the find command I need exactly X iterations of the for loop.

What I'm looking for is a way to iterate through all mp3 files in a directory, then perform some tagging on each one individually. This gets quite complex as I have to formulate the tag data from the file name itself, then call id3v2 with the appropriate switches and tag strings. So far haven't managed to get find working the way I want it to, and -exec {} hasn't really helped me either yet.

osor · 10-04-2007, 05:00 PM

Quote:

Originally Posted by sir_woland

So far haven't managed to get find working the way I want it to, and -exec {} hasn't really helped me either yet.

What’s the problem with exec? Maybe I don’t correctly understand you, but does this not do what you want?:

Code:

find . -iname "*.mp3" -exec do_tagging \"{}\" \;

syg00 · 10-04-2007, 05:04 PM

Change the default field separator to newline - then your original should work.
Pays to save and restore the IFS value, but that's just personal preference.

sir_woland · 10-04-2007, 05:26 PM

Yes! Changing the IFS was precisely the correct thing to do, and running the script in a subshell lets me use the new IFS value only for the duration of the script. Works perfectly, thank you!

The reason -exec didn't fly is that the tagging command I need to run for each and every file is of the form:

Code:

id3v2 -T tracknum -t "trackname" file_to_process

where tracknum and trackname are strings cut from the file name and piped through tr and sed. Too much for my inept skills!

jschiwal · 10-04-2007, 05:33 PM

I will do it like this:
You can use the -print0 option to use a null instead of a carriage return. The list can be fed to xargs with the -0 option.

If the source or filenames is another command you can pipe the output through "| tr '\n' '\000' |"
example:
find . -iname "*.mp3" -print0 | xargs -0 mpg2ogg

When I use K3B to make a backup of a directory, I'll save the .k3b file and unzip it and use sed to obtain the filenames backed up. Then I can pipe the output through "| tr '\n' '\000' | xargs -0 rm -v" to remove the files backed up.

osor · 10-04-2007, 07:10 PM

I’m glad you found a solution that suits you.

Quote:

Originally Posted by sir_woland

The reason -exec didn't fly is that the tagging command I need to run for each and every file is of the form:

Code:

id3v2 -T tracknum -t "trackname" file_to_process

where tracknum and trackname are strings cut from the file name and piped through tr and sed. Too much for my inept skills!

If you wanted to do it cleanly, this would work:

Code:

find . -iname "*.mp3" -exec ./do_tagging \"{}\" \;

Where the file do_tagging is something like this:

Code:

#!/bin/sh

tracknum=$(echo "$1" | tr '1' '2' | sed 's/foo/bar')
trackname=$(echo "$1" | tr '3' '4' | sed 's/foo/bar')

id3v2 -T $tracknum -t "$trackname" $1

I guess that is a little too roundabout.