Use xargs if IF statements is inside the program code

Question

There is a program like this:

while true
do
    echo 'Your pass: '
    read password
    if [ $password == 'qwerty' ]; then 
        echo 'Nice!'
        break
    fi
done

I can use xargs only if the program has arguments. But in this case ./program.sh password doesn't work. I have a list of password and I need to send them in loop to this program.

xargs -a list ./program.sh doesn't work.

Answer 1

There's no reason to use xargs here, you can simply do:

while IFS= read -r password
do
    if [ "$password" = 'qwerty' ]; then 
        echo 'Nice!'
        break
    fi
done

And then run it as:

./program.sh < list

If you really want xargs, you can do something like:

for password do
  case "$password" in
    'qwerty')
      echo 'Nice!'
      ;;
  esac
done

And then:

xargs -rd '\n' -a list ./program.sh