Assign output of a shell command to a variable

Question

I want to assign the output of a shell command to a variable.

If I directly echo the command, the code will execute correctly:

for ((i=0; i<${#result[@]}; i++)); do
    echo ${result[$i]} | awk '{print $1}'
    done

But, if I assign it to a variable,

size=`${result[$i]} | awk '{print $1}'`
echo $size

Or

size=$(${result[$i]} | awk '{print $1}')
echo $size

They are not working.

How can I fix it?

Answer 1

You missed the echo

size=$(echo ${result[$i]} | awk '{print $1}')

---

Here the output the the echo is passed as input to the awk

The $() or back ticks just run the command and assign it to a variable, so when you just write

${result[$i]} | awk '{print $1}'

it won't give you anything as nothing is passed as input to the awk command.