prepend filename, not destination path, using mv

Question

In the process of posting this question I've been experimenting with my code, I've come up with something that works, but my restless intellect wants to be a better programmer, not just solve the problem at hand, so I'm posting Script 1.0 and Script 1.1 to ask the community, Why does the change to line 3 make it work?

I'm copying files from a server and renaming them. The copying is going fine; the renaming isn't. These filenames have spaces. cp handles them competently; mv seems throws an error. I expected putting "" around the variable name to resolve the issue, but it still gives an error: mv: rename /src/foo.wav to zzz - /dest/foo.wav - copied 201403261800.wav: No such file or directory. I'm trying to prepend "zzz" to the filename, but it's getting prepended to the destination path. Here's Script 1.0:

cd /src/
DATE=$(date +"%Y%m%d%H%M")
find . -type f -iname "*.wav" | while read file ; do
    if [[ "$file" != *zzz* ]]; then
        echo "Tranferring...";
        cp "$file" /dest/
        mv "$file" \zzz\ \-\ "$file"\ \-\ copied\ $DATE.wav
        echo "Transfer complete.";
    fi
done 

(The if condition ensures that I don't re-copy anything I've previously copied and renamed.)

Changing the 3rd line makes it work. But why? Here's Script 1.1:

cd /src/
DATE=$(date +"%Y%m%d%H%M")
find *.* -iname "*.wav" | while read file ; do
    if [[ "$file" != *zzz* ]]; then
        echo "Tranferring...";
        cp "$file" /dest/
        mv "$file" \zzz\ \-\ "$file"\ \-\ copied\ $DATE.wav
        echo "Transfer complete.";
    fi
done 

Answer 1

If you look at the output of the different find commands you'll see that find . -type f will return lines like this: ./passwd. Now you can't use that as the target, as renaming ./passwd to zzz - ./passwd would try to move it to a zzz - . folder as passwd.

By the way, you can surround the whole target name with quotes, to make it look better (also you should not escape the first z anyway):

mv "$file" "zzz - $file - copied $DATE.wav"

Also you probably want to get rid of the .wav part in the middle of the file:

mv "$file" "zzz - ${file%.wav} - copied $DATE.wav"

The ${var%string} returns the value of $var with string removed from the end of it if present. You can find more about this looking for bash string manipulation.