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loop over a set of items that contain spaces

Terminal - loop over a set of items that contain spaces
ls | while read ITEM; do echo "$ITEM"; done
2009-03-22 23:33:13
User: fletch
Functions: echo ls read
9
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loop over a set of items that contain spaces

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
Show sample output | Add to favourites | Report as malicious

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

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.

Comment by goodevilgenius 221 weeks and 2 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.

Comment by haivu 221 weeks and 2 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!

Comment by pixelbeat 221 weeks and 2 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.

Comment by fletch 221 weeks and 1 day ago

Your point of view

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