Linux/Bash: How to unquote?

Question

Following command

echo 'a b' 'c'

outputs

a b c

But the following

X="'a b' 'c'"
echo $X;

will outout

'a b' 'c'

I am searching a way to unquote $X , so that it will output "a b c" , but without losing the merged 'a b' argument. (= 2 arguments instead of 3, makes no difference for command 'echo', but for other commands like 'cp')

Solution 1

Try xargs:

$ echo $x
'a b' 'c'

$ echo $x | xargs ./echo
argc = 3
argv[0] = ./echo
argv[1] = a b
argv[2] = c

Solution 2

eval echo $x

this will pass a b as first argument and c as the second one

Note: this will actually evaluate arguments, eg:

$ x='$((3+5))'
$ eval echo $x
8

If that's not what you want use @vanza's xargs.

Solution 3

Usually, if you're trying to store multiple "words" in a single variable, the recommended method isn't to use embedded quotes, but to use an array:

X=('a b' 'c')
printf "%s\n" "${X[@]}"

prints:

a b
c