Hiding a user input

login.cpp

// source: https://stackoverflow.com/questions/6899025/hide-user-input-on-password-prompt

#include <iostream>
#include <string>

#ifdef WIN32    // Windows
#include <windows.h>
#else           // Unix = Linux / Mac OS
#include <termios.h>
#include <unistd.h>
#endif

using namespace std;        // Do not use this! Rather use direct reference as std::reference!

void hide_input(void);
void show_input(void);

int main(void)
{
    string uname, passw;
    cout << "Login > ";
    getline(cin, uname);
    
    hide_input();
    cout << "Password > "
    getline(cin, passw);
    show_input();
    
    cout << "Your login is '" << uname << "'." << endl;
    cout << "Your password is '" << passw << "'." << endl;
    
    return 0;
}

#ifdef WIN32
void hide_input(void)
{
    HANDLE hStdin = GetStdHandle(STD_INPUT_HANDLE);
    DWORD mode = 0;
    GetConsoleMode(hStdin, &mode);
    SetConsoleMode(hStdin, mode & (~ENABLE_ECHO_INPUT));
}

void show_input(void)
{
    HANDLE hStdin = GetStdHandle(STD_INPUT_HANDLE);
    DWORD mode = 0;
    GetConsoleMode(hStdin, &mode);
    SetConsoleMode(hStdin, mode | (ENABLE_ECHO_INPUT));
}
#else
void hide_input(void)
{
    termios terminal_mode;
    tcgetattr(STDIN_FILENO, &terminal_mode);
    terminal_mode.c_lflag &= ~ECHO;
    tcsetattr(STDIN_FILENO, TCSANOW, &terminal_mode);
}

void show_input(void)
{
    termios terminal_mode;
    tcgetattr(STDIN_FILENO, &terminal_mode);
    terminal_mode.c_lflag |= ECHO;
    tcsetattr(STDIN_FILENO, TCSANOW, &terminal_mode);
}
#endif

OS Branching would not be used in real project directly in source code, just in Makefile to include appropriate libraries for Windows and Linux.

In real project, this method would be separated between login.h with raw definitions and login.win32.cpp and login.linux-i386.cpp with OS dependent implementations.