Bash script - how to fill array?

Question

Let's say I have this directory structure:

DIRECTORY:

.........a

.........b

.........c

.........d

What I want to do is: I want to store elements of a directory in an array

something like : array = ls /home/user/DIRECTORY

so that array[0] contains name of first file (that is 'a')

array[1] == 'b' etc.

Thanks for help

This may be helpful: http://tldp.org/LDP/abs/html/arrays.html. Use a `for` loop to iterate through the return values of `ls`. — drewmm, Apr 10 '13 at 17:21
This may be helpful too; http://stackoverflow.com/questions/9954680/how-to-store-directory-files-listing-into-an-array — , Apr 10 '13 at 17:22
This may be helpful too: https://linuxconfig.org/how-to-use-arrays-in-bash-script — Antônio Medeiros, Sep 16 '19 at 17:15

score 14 · Accepted Answer · answered Apr 10 '13 at 17:37

You can't simply do array = ls /home/user/DIRECTORY, because - even with proper syntax - it wouldn't give you an array, but a string that you would have to parse, and Parsing ls is punishable by law. You can, however, use built-in Bash constructs to achieve what you want :

#!/usr/bin/env bash

readonly YOUR_DIR="/home/daniel"

if [[ ! -d $YOUR_DIR ]]; then
    echo >&2 "$YOUR_DIR does not exist or is not a directory"
    exit 1
fi

OLD_PWD=$PWD
cd "$YOUR_DIR"

i=0
for file in *
do
    if [[ -f $file ]]; then
        array[$i]=$file
        i=$(($i+1))
    fi
done

cd "$OLD_PWD"
exit 0

This small script saves the names of all the regular files (which means no directories, links, sockets, and such) that can be found in $YOUR_DIR to the array called array.

Hope this helps.

It works, but only for files. I would also like to store name of a directory to array (if there is any) — user1926550, Apr 10 '13 at 17:52
Just modify the `if` in the loop according to your needs, then. — Daniel Kamil Kozar, Apr 10 '13 at 17:55

score 6 · Answer 2 · edited Oct 27 '17 at 10:11

Option 1, a manual loop:

dirtolist=/home/user/DIRECTORY
shopt -s nullglob    # In case there aren't any files
contentsarray=()
for filepath in "$dirtolist"/*; do
    contentsarray+=("$(basename "$filepath")")
done
shopt -u nullglob    # Optional, restore default behavior for unmatched file globs

Option 2, using bash array trickery:

dirtolist=/home/user/DIRECTORY
shopt -s nullglob
contentspaths=("$dirtolist"/*)   # This makes an array of paths to the files
contentsarray=("${contentpaths[@]##*/}")  # This strips off the path portions, leaving just the filenames
shopt -u nullglob    # Optional, restore default behavior for unmatched file globs

score 2 · Answer 3 · answered Dec 15 '20 at 14:47

2

array=($(ls /home/user/DIRECTORY))

Then

echo ${array[0]}

will equal to the first file in that directory.

answered Dec 15 '20 at 14:47

chunky_pie

41
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Bash script - how to fill array?

3 Answers3