Question

Hi I am trying to create a bash program to call a program and input menu picks into it.

For example my program runs

Hello world:
1) Item 1
2) Item 2
Enter : 2

Item 2 Menu
1) sub Item A
2) sub item B
enter: 1

I tried doing $ 2|1|./program and $./program|2|1

But it either fails or it just loops forever and doesn’t get to the second menu.

Is it possible to do this?

Answer 1

Presuming a program that works essentially like this one:

pmenu () {
    printf '%s) %s\n' "$1" "$2"
}

m1 () {
    pmenu 1 'Item 1'
    pmenu 2 'Item 2'
}
m2 () {
    pmenu 1 'sub Item A'
    pmenu 2 'sub Item B'
}

printf 'Hello, World:\n'

m1
read -p "enter: " m

case "$m" in
    1 ) m2 ;;
    2 ) m2 ;;
esac

read -p "enter: " m

echo "You chose: $m"

Then you can just say

printf '2\n1\n' | program

For anything less straightforward you may need to learn expect, which is designed for this sort of thing.