CODEWITHSUNDEEP
shell
jb_alvarado
jb_alvarado

Reputation: 179

shell: build variable with multiple paths and commands

Is there a way to build a varible like this:

var="-i \"/path to/file 1.mp4\" -i \"/path to/file 2.mp4\""

And then use this later in a program:

ffmpeg $var

I know \" doesn't work, and eval works in a way, but eval can be ugly.

Is there a solution without eval?

Upvotes: 0

Views: 75

Answers (1)

Dennis B.
Dennis B.

Reputation: 1577

The next best thing to do is to build an array. When you put ${var[@]} somewhere, it will replace it with the complete array contents. If you put "${var[@]}" somewhere (with quotes), the elements of the array will be quoted, so elements with spaces will not be split at the whitespace into multiple elements:

#!/bin/bash

function test() {
    for ((i=0; i<$#; i++)) {
        echo "Param $i: ${!i}"
    }
}

var[0]="-i"
var[1]="/a/path"
var[2]="-i"
var[3]="/second/path with space/"

test "${var[@]}"

Will output:

Param 0: test.sh
Param 1: -i
Param 2: /a/path
Param 3: -i

and that is exactly what you require. I only tried this in bash, other shells may behave differently.

Upvotes: 1

Related Questions