How can I use the backspace character as a backspace when entering a password? [closed]

Question

I just saw this code somewhere.
It allows the user to enter his password and change it to an asterisk/star.
But it doesn't recognize the backspace key.
The code thinks that the backspace is part of the password.
What should I do to make it recognize the backspace?
And can someone explain this code to me?
Especially the IFS, the options of read, and the $'\0'
Thanks!

Here is the code.

\#!/bin/bash
unset password
prompt="Enter Password:"
while IFS= read -p "$prompt" -r -s -n 1 char
do
if [[ $char == $'\0' ]]
then
    break
fi
prompt='*'
password+="$char"
done
echo
echo "Done. Password=$password"

Answer 1

Try this:

#!/bin/bash
unset password
prompt="Enter Password:"
while IFS= read -p "$prompt" -r -s -n 1 char 
do
    if [[ $char == $'\0' ]];     then
        break
    fi
    if [[ $char == $'\177' ]];  then
        prompt=$'\b \b'
        password="${password%?}"
    else
        prompt='*'
        password+="$char"
    fi
done
echo " "
echo "Done. Password=$password" 

The options of the read command are:
-p : Prompt string.
-r : Don't use backslash as escape character.
-s : Silent mode, inputs are not echoed.
-n 1 : Number of character to input.

read returns 0 unless \0 is encountered, and the character the user types is placed into the char variable.

The IFS= part clears the IFS variable, which ensures that any space or tab characters that you type are included in the password rather than being parsed out by read.