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#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>

/* Use this variable to remember original terminal attributes. */

struct termios saved_attributes;

    void
reset_input_mode (void)
{
    tcsetattr (STDIN_FILENO, TCSANOW, &saved_attributes);
}

    void
set_input_mode (void)
{
    struct termios tattr;
    char *name;

    /* Make sure stdin is a terminal. */
    if (!isatty (STDIN_FILENO))
    {
        fprintf (stderr, "Not a terminal.\n");
        exit (EXIT_FAILURE);
    }

    /* Save the terminal attributes so we can restore them later. */
    tcgetattr (STDIN_FILENO, &saved_attributes);
    atexit (reset_input_mode);

    /* Set the funny terminal modes. */
    tcgetattr (STDIN_FILENO, &tattr);
    tattr.c_lflag &= ~(ICANON|ECHO); /* Clear ICANON and ECHO. */
    tattr.c_cc[VMIN] = 1;
    tattr.c_cc[VTIME] = 0;
    tcsetattr (STDIN_FILENO, TCSAFLUSH, &tattr);
}

    int
main (void)
{
    char c;

    set_input_mode ();

    while (1)
    {
        read (STDIN_FILENO, &c, 1);
        if (c == EOF || c == '\n')          /* C-d */
            break;
        else
        {
            putchar('*');
            fflush(NULL);
        }
    }

    return EXIT_SUCCESS;
}