split command output into array of lines

Question

Here's my bash function to get a command's output as parameter and then return an array of output lines.

function get_lines { 
    while read -r line; do 
        echo $line
    done <<< $1
}

SESSIONS=`loginctl list-sessions`
get_lines "$SESSIONS"

Actual output of loginctl list-sessions is:

   SESSION        UID USER             SEAT            
        c2       1000 asif             seat0           
        c7       1002 sadia            seat0           

But the while loop only runs once printing all output in a single line. How can I get an array of lines and return it?

Answer 1

You could use readarray and avoid the get_lines function:

readarray SESSIONS < <(loginctl --no-legend list-sessions)

this create the array SESSIONS with each line of the output of the command mapped to an element of the array.