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Bash array with spaces in elements

I think the issue might be partly with how you're accessing the elements. If I do a simple for elem in $FILES, I experience the same issue as you. However, if I access the array through its indices, like so, it works if I add the elements either numerically or with escapes:

for ((i = 0; i < ${#FILES[@]}; i++))
do
    echo "${FILES[$i]}"
done

Any of these declarations of $FILES should work:

FILES=(2011-09-04\ 21.43.02.jpg
2011-09-05\ 10.23.14.jpg
2011-09-09\ 12.31.16.jpg
2011-09-11\ 08.43.12.jpg)

or

FILES=("2011-09-04 21.43.02.jpg"
"2011-09-05 10.23.14.jpg"
"2011-09-09 12.31.16.jpg"
"2011-09-11 08.43.12.jpg")

or

FILES[0]="2011-09-04 21.43.02.jpg"
FILES[1]="2011-09-05 10.23.14.jpg"
FILES[2]="2011-09-09 12.31.16.jpg"
FILES[3]="2011-09-11 08.43.12.jpg"

There must be something wrong with the way you access the array's items. Here's how it's done:

for elem in "${files[@]}"
...

From the bash manpage:

Any element of an array may be referenced using ${name[subscript]}. ... If subscript is @ or *, the word expands to all members of name. These subscripts differ only when the word appears within double quotes. If the word is double-quoted, ${name[*]} expands to a single word with the value of each array member separated by the first character of the IFS special variable, and ${name[@]} expands each element of name to a separate word.

Of course, you should also use double quotes when accessing a single member

cp "${files[0]}" /tmp

You need to use IFS to stop space as element delimiter.

FILES=("2011-09-04 21.43.02.jpg"
       "2011-09-05 10.23.14.jpg"
       "2011-09-09 12.31.16.jpg"
       "2011-09-11 08.43.12.jpg")
IFS=""
for jpg in ${FILES[*]}
do
    echo "${jpg}"
done

If you want to separate on basis of . then just do IFS="." Hope it helps you:)


I agree with others that it's likely how you're accessing the elements that is the problem. Quoting the file names in the array assignment is correct:

FILES=(
  "2011-09-04 21.43.02.jpg"
  "2011-09-05 10.23.14.jpg"
  "2011-09-09 12.31.16.jpg"
  "2011-09-11 08.43.12.jpg"
)

for f in "${FILES[@]}"
do
  echo "$f"
done

Using double quotes around any array of the form "${FILES[@]}" splits the array into one word per array element. It doesn't do any word-splitting beyond that.

Using "${FILES[*]}" also has a special meaning, but it joins the array elements with the first character of $IFS, resulting in one word, which is probably not what you want.

Using a bare ${array[@]} or ${array[*]} subjects the result of that expansion to further word-splitting, so you'll end up with words split on spaces (and anything else in $IFS) instead of one word per array element.

Using a C-style for loop is also fine and avoids worrying about word-splitting if you're not clear on it:

for (( i = 0; i < ${#FILES[@]}; i++ ))
do
  echo "${FILES[$i]}"
done

If you had your array like this: #!/bin/bash

Unix[0]='Debian'
Unix[1]="Red Hat"
Unix[2]='Ubuntu'
Unix[3]='Suse'

for i in $(echo ${Unix[@]});
    do echo $i;
done

You would get:

Debian
Red
Hat
Ubuntu
Suse

I don't know why but the loop breaks down the spaces and puts them as an individual item, even you surround it with quotes.

To get around this, instead of calling the elements in the array, you call the indexes, which takes the full string thats wrapped in quotes. It must be wrapped in quotes!

#!/bin/bash

Unix[0]='Debian'
Unix[1]='Red Hat'
Unix[2]='Ubuntu'
Unix[3]='Suse'

for i in $(echo ${!Unix[@]});
    do echo ${Unix[$i]};
done

Then you'll get:

Debian
Red Hat
Ubuntu
Suse