loop over a set of items that contain spaces

ls | while read ITEM; do echo "$ITEM"; done
If you want to operate on a set of items in Bash, and at least one of them contains spaces, the `for` loop isn't going to work the way you might expect. For example, if the current dir has two files, named "file" and "file 2", this would loop 3 times (once each for "file", "file", and "2"): for ITEM in `ls`; do echo "$ITEM"; done Instead, use a while loop with `read`: ls | while read ITEM; do echo "$ITEM"; done
Sample Output
file 2

By: fletch
2009-03-22 23:33:13

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What Others Think

I think I might prefer: find . -maxdepth 1 -exec {} \; You don't even have to worry about the quote. "find" takes care of it for you. However, if I wanted to perform multiple operations on one set of items, I would definitely use this method you suggested.
goodevilgenius · 478 weeks and 5 days ago
@fletch: As you said, the following does not work: for FILE in `ls`; do echo "$FILE"; done But the following will work: for FILE in *; do echo "$FILE"; done However, I also acknowledge that your way works.
haivu · 478 weeks and 5 days ago
Grr why is this being upmodded? Unixmonkey1878's method is the right way to do this. ls is for presenting a directory listing to humans, that's it!
pixelbeat · 478 weeks and 5 days ago
You're all correct, there are other ways to do that particular example. Your methods only work for a list of files though, and the intent was to show a way to iterate over a any list of items that have spaces. `ls` could have been any command.
fletch · 478 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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