Comment by gfunk911

  # Retries a command a with backoff.
  #
  # The retry count is given by ATTEMPTS (default 100), the
  # initial backoff timeout is given by TIMEOUT in seconds
  # (default 5.)
  #
  # Successive backoffs increase the timeout by ~33%.
  #
  # Beware of set -e killing your whole script!
  function try_till_success {
    local max_attempts=${ATTEMPTS-100}
    local timeout=${TIMEOUT-5}
    local attempt=0
    local exitCode=0

    while [[ $attempt < $max_attempts ]]
    do
      "$@"
      exitCode=$?

      if [[ $exitCode == 0 ]]
      then
        break
      fi

      echo "Failure! Retrying in $timeout.." 1>&2
      sleep $timeout
      attempt=$(( attempt + 1 ))
      timeout=$(( timeout * 40 / 30 ))
    done

    if [[ $exitCode != 0 ]]
    then
      echo "You've failed me for the last time! ($@)" 1>&2
    fi

    return $exitCode
  }