Shell Programming and Scripting

$ cat step_restart_straight
#!/bin/ksh
# Just a quick step-restart demo

step="${1:-0}"

# Section 1
if [ $step -ge 1 ]
then
   echo "This is running Section 1."
fi

# Section 2
if [ $step -ge 2 ]
then
   echo "This is running Section 2."
fi

# Section 3
if [ $step -ge 3 ]
then
   echo "This is running Section 3."
fi

# Section 4
if [ $step -ge 4 ]
then
   echo "This is running Section 4."
fi
$ step_restart_straight
This is running Section 1.
This is running Section 2.
This is running Section 3.
This is running Section 4.
$
$ step_restart_straight 3
This is running Section 3.
This is running Section 4.
$

cat step_restart_functions
#!/bin/ksh
# Just a quick step-restart demo

function_one()
{
 echo "This is function 1"
}

function_two()
{
 echo "This is function $step."
}

function_three()
{
 echo "This is function $step."
}

function_four()
{
 echo "This is function 4"
}

step="${1:-0}"

while :
do
 case $step in
  0) : ;;                          # No action for zero step
  1) function_one ;;
  2) function_two ;;
  3) function_three ;;
  4) function_four ;;
  *) exit ;;
 esac

 ((step=$step +1))            # Increment count to go to next step
done                               # Go round and run next step
$ step_restart_functions  
This is function 1
This is function 2.
This is function 3.
This is function 4
$
$ step_restart_straight 3
This is function 3.
This is function 4
$