How do I make password prompts not echo back the user?

[reyjrar]

so, I'm doing the whole talker thing and one thing I've always found annoying about some talkers is that when you are prompted for your passwd, it echoes the letters back to the screen. I know its possible in c to just turn the echo off temporarily, that way you can type your passwd and not have everyone looking over your shoulder see it.
anyone know how to do that in perl?

thanks,
-brad..

Originally posted as a Categorized Question.

[Shendal]

Use Term::Readkey. It is more portable than the unix-only solution of stty. Here's a quick example (untested):


use Term::ReadKey;
print "Type your password:";
ReadMode('noecho'); # don't echo
chomp(my $password = <STDIN>);
ReadMode(0);        # back to normal


Cheers,
Shendal

[isotope]

You might want to try something more like:

use Term::ReadKey;
ReadMode('noecho'); # don't echo
print "Type your password:";
chomp(my $password = <STDIN>);
ReadMode(0);        # back to normal

...so you only print the password prompt when echo has already been disabled. This makes your program more compatible with things like Expect, which may not wait long enough after the prompt for the echo to be disabled before sending the password.

--isotope
http://www.skylab.org/~isotope/

[Anonymous Monk]

Here's how I did it using Term::Readkey

ReadMode ('noecho');
print "Enter Password: ";
chomp($pw = <STDIN>);
ReadMode ('restore');

[batkins]

Another methood is this:

system('stty -echo');
print "Enter Password: ";
chomp($pw = <STDIN>);
system('stty echo');

[skx]

 This works but there are two caveats you should bear in mind:

• If you're running the script as a priviledged process you might have just opened yourself to a local attack, if the user can modify their path and slip in a trojan 'stty' binary.
• This fails utterly on Windows, amongst other systems.

[I0]

use Term::ReadPassword;

[Fastolfe]

The easiest solution, under Unix at least, is to call 'stty' to change the terminal's "echo" attribute. I know of no way to do this under Windows or any non-Unix platform, and there may be a more standardized way of doing this (such as via curses or some Term-based module):

print "login: "
my $login = <>;
print "Password: "
system('/usr/bin/stty', '-echo');  # Disable echoing
my $password = <>;
system('/usr/bin/stty', 'echo');   # Turn it back on

[strredwolf]

In addition to Term::Readkey, you may want to write up your own linegetter with getc(STDIN). That way, you'll be able to trap all of the deletes/backspaces w/o having any problems.

Isn't there a Readline module?