How to pass a variable which has multiple arguments to function all at once?

Question

I am trying to make a command which allows the user to input a name as the first argument for the compressed file they want to create (which will become a tar.gz file) and file and directory names as the second argument.

So far I have this script

name_of_archive=$1
directory_or_file_paths=$2

if [ $# -eq 0 ]
then
        echo "Usage: $0 [name of archive you wish to create] [path of directories or files you wish to compress]"
        echo "You must enter atleast one file or directory name"
        exit 1
else
        if [ -e "$directory_or_file_paths" ] || [ -d "$directory_or_file_paths" ]
        then
                tar -czvf "$name_of_archive".tar.gz "$directory_or_file_paths"
                echo "The filenames or directories you specified have been compressed into an archive called $name_of_archive.tar.gz"
        else
                echo "Some or all of the file or directory names you have given do not exist"
        fi
        exit
fi

This is what I get when I use the command:

compression2.bash compression1 ./test ./listwaste
./test/
./test/test2/
./test/test2/2
./test/1
The filenames or directories you specified have been compressed into an archive called compression1.tar.gz

The first is a directory and the second is a file. It works if I attempt to compress both individually but does not work if I try to compress more than one file or directory or a mix at a time. I would like it to be able to do that.

Answer 1

It is not a good idea to store filenames in a string. Storing them in an array is a much better approach:

#!/usr/bin/env bash

[[ $# -lt 2 ]] && exit 1

name=$1; shift
files=("$@")

#exclude all files/directories that are not readable
for index in "${!files[@]}"; do
   [[ -r ${files[index]} ]] || unset "files[index]"
done

[[ ${#files[@]} -eq 0 ]] && exit 1    

if tar -czvf "${name:-def_$$}.tar.gz" "${files[@]}"; then
   echo "Ok"
else
   echo "Error"
   exit 1
fi

shift; files=("$@") discards the first argument (name) and saves the rest of the arguments (filenames) into an array.

---

You could also construct the array of filenames for tar with a more straightforward approach:

name=$1; shift

for file; do
   [[ -r $file ]] && files+=("$file")
done

Answer 2

That is because you are only looking at the 2nd parameter and putting it in your directory_or_file_paths variable. Whenever Linux finds a space in your command, it treats it as another parameter so you are not even looking at these other files or folders. What you will need to do is, if the number of params is not 0, and you have the first one as your name_of_archive, then you will need to loop through all the remaining parameters and construct a string that includes them all, separated by spaces and this is what you will give as a param to the tar command.

Answer 3

I think you want to use shift after getting the first input into your variable name for the archive. You can then pass the whole list, instead of only one argument for the archive.

name_of_archive=$1
shift
directory_or_file_paths=("$@")
...

https://ss64.com/bash/shift.html