Hide password input on terminal

Question

I want to mask my password while writing it with *. I use Linux GCC for this code. I know one solution is to use getch() function like this

Answer 1

In the Linux world, masking isn't usually done with asterisks, normally echoing is just turned off and the terminal displays blanks E.g. if you use su or log into a virtual terminal etc.

There is a library function to handle getting passwords, it won't mask the password with asterisks but will disable echoing of the password to terminal. I pulled this out of a linux book I have. I believe its part of the posix standard

#include 
char *getpass(const char *prompt);

/*Returns pointer to statically allocated input password string
on success, or NULL on error*/

The getpass() function first disables echoing and all processing of terminal special characters (such as the interrupt character, normally Control-C).

It then prints the string pointed to by prompt, and reads a line of input, returning the null-terminated input string with the trailing newline stripped, as its function result.

A google search for getpass() has a reference to the GNU implementation (should be in most linux distros) and some sample code for implementing your own if need be

http://www.gnu.org/s/hello/manual/libc/getpass.html

Their example for rolling your own:

#include 
#include 

ssize_t
my_getpass (char **lineptr, size_t *n, FILE *stream)
{
    struct termios old, new;
    int nread;

    /* Turn echoing off and fail if we can't. */
    if (tcgetattr (fileno (stream), &old) != 0)
        return -1;
    new = old;
    new.c_lflag &= ~ECHO;
    if (tcsetattr (fileno (stream), TCSAFLUSH, &new) != 0)
        return -1;

    /* Read the password. */
    nread = getline (lineptr, n, stream);

    /* Restore terminal. */
    (void) tcsetattr (fileno (stream), TCSAFLUSH, &old);

    return nread;
}

If need be you could use this as the basis as modify it to display asterisks.