Bash array with spaces in elements

Question

I m trying to construct an array in bash of the filenames from my camera   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    As you can see  there is a space in the middle of each filename   I ve tried wrapping each name in quotes  and escaping the space with a backslash  neither of which works   When I try to access the array elements  it continues to treat the space as the elementdelimiter   How can I properly capture the filenames with a space inside the name

User · Accepted Answer

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"

User · Answer

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  lt     FILES      i      do   echo    FILES  i    done

User · Answer

Escaping works      bin bash  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   echo   FILES 0   echo   FILES 1   echo   FILES 2   echo   FILES 3     Output       test sh 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   Quoting the strings also produces the same output

User · Answer

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

User · Answer

Another solution is using a  while  loop instead a  for  loop   index 0 while     index  -lt    Array         do      echo   Array   index         index      index   1      done

User · Answer

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

User · Answer

I used to reset the IFS value and rollback when done    backup IFS value O IFS  IFS    reset IFS value IFS  quot  quot   FILES    quot 2011-09-04 21 43 02 jpg quot   quot 2011-09-05 10 23 14 jpg quot   quot 2011-09-09 12 31 16 jpg quot   quot 2011-09-11 08 43 12 jpg quot     for file in   FILES      do     echo   file  done    rollback IFS value IFS   O IFS   Possible output from the loop   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

User · Answer

If you aren t stuck on using bash  different handling of spaces in file names is one of the benefits of the fish shell  Consider a directory which contains two files   a b txt  and  b c txt   Here s a reasonable guess at processing a list of files generated from another command with bash  but it fails due to spaces in file names you experienced     bash   for f in   ls   txt     echo  f    a b txt b c txt    With fish  the syntax is nearly identical  but the result is what you d expect     fish for f in  ls   txt   echo  f  end a b txt b c txt   It works differently because fish splits the output of commands on newlines  not spaces    If you have a case where you do want to split on spaces instead of newlines  fish has a very readable syntax for that   for f in  ls   txt   string split       echo  f  end

User · Answer

Not exactly an answer to the quoting escaping problem of the original question but probably something that would actually have been more useful for the op   unset FILES for f in 2011-  jpg  do FILES     f    done echo    FILES        Where of course the expression would have to be adopted to the specific requirement  e g    jpg for all or 2001-09-11  jpg for only the pictures of a certain day

User · Answer

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

[arrays] Bash array with spaces in elements

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