05-Loops-While.md

While Loop

• Help me to understand the while loop

• While loop works just like the for loop, except theat it executes the loop as long as the condition is true.

• Execute a command or a set of commands multiple times but you are not sure how many times.

• Execute a command or a set of commands until a specific condition occurs

• Create infinite loops

• Menu driven programs

  Examples of while loop

  mission_name=$1
  
  mkdir $mission_name
  
  rocket-add $mission_name
  
  rocket-start-power $mission_name
  rocket-internal-power $mission_name
  rocket-start-sequence $mission_name
  rocket-start-engine $mission_name
  rocket-lift-off $mission_name
  rocket_status=rocket-status $mission_name
  
  while [ $rocket_status = "launching" ]
  do
   sleep 2
   rocket_status=rocket-status $mission_name
  done
  
  if [ $rocket_status = "failed" ]
  then
    rocket-debug $mission_name
  fi
  

  

• Real life use case can be :