Bash pipe tail file while loop read line

pipe_tail_read_file.sh

#!/bin/bash

# read from stdin
while read line
do
  echo "$line"
done < "${1:-/dev/stdin}"

# read from file
while read line
do
  echo "$line"
done < <(tail -f data.txt)

# read from file also
tail -f data.txt | while read line
do
    echo "$line"
done