Shell script - while loop example

while_loop_example.sh

#!/bin/sh

MAX_TRIES=100
TRIES=0
OUTPUT=/tmp/output.txt

while [ $TRIES -lt $MAX_TRIES ]
do
  # run some command here, "ls -l" is used below
  ls -l
  
  EXIT_VAL=$?
  echo "********************"
  echo "EXIT_VAL: ${EXIT_VAL}"
  if [ $EXIT_VAL -ne 0 ]
  then
    echo $OUTPUT
    # say command only works on Mac
    say "A failure happened.  Awesome"
  fi

  TRIES=`expr $TRIES \+ 1`
  echo "Num tries: ${TRIES}"
done