input password with astrix

Question

I want to read char one by one and show to astrix *. Characters can be showed as *, but I cannot exit by pushing Enter.

This is my code:

import sys, tty, termios

def getch():
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    try:
        tty.setraw(sys.stdin.fileno())
        ch = sys.stdin.read(1)
        sys.stdout.write('*')
    except:
        print "ex"
    finally:
        termios.tcsetattr(fd, termios.TCSADRAIN,old_settings)
    return ch

If I input Enter where ch = sys.stdin.read(1), what is the return value?

Answer 1

You can use getpass.getpass to prompt a user for a password. But note that getpass module does not show asterisks for unix password prompts.

As for the second part of the question - sys.stdin.read(1) returns \n or \r for Enter input, it depends on a terminal you're using.

And, finally, I made an example how to use your function to read until CR or LF:

while True:', '\n']: break
    ch = getch()
    if ch in ['\r', '\n']: break
    sys.stdout.flush()

If you really need to show asterisks even for unix, that's the way.