Run a program until some output string is found

executeUntilString.sh

#!/bin/bash
counter=0
while true; do
    counter=$((counter + 1))
    output=$(./MyApp)  # Execute the program and store its output
    last_line=$(echo "$output" | tail -n 1)  # Extract the last line of the output
    echo "$output"  # Print the output

    if [ "$last_line" == "output" ]; then # Change this string to desired match
        echo "Output found after: $counter" # Shows number of program executions
        break  # Exit the loop if the last line is "output"
    fi
done