Disabling echo for password prompts

To protect users' passwords from shoulder surfing, it's always best to hide what they type. The way to hide a password from being displayed is to disable echoing. In this recipe, we'll write a simple password program with echoing disabled.

Knowing how to disable echoing is key when writing programs that take some form of secret input, such as a password or a key.

Getting ready

For this recipe, you'll need the GCC compiler, the Make tool, and the generic Makefile.

How to do it…

In this recipe, we'll build a small program with a password prompt

1. Since the code in this recipe will be rather long and some parts a bit arcane, I have split up the code into several steps. Note, however, that all code should go into a single file. Name the file passprompt.c. Let's start with the include lines, the main() function, and the variables we'll need. The struct named term of type termios is a special...