Using the passwd command from within a shell script

bash, linux, shell, unix

Solution

from "`man 1 passwd`":

   --stdin
          This option is used to indicate that passwd should read the new
          password from standard input, which can be a pipe.

So in your case

adduser "$1"
echo "$2" | passwd "$1" --stdin

Your `passwd` command may not have a `--stdin` option: use the `chpasswd` utility instead, as suggested by ashawley.

If you use a shell other than bash, `echo` might not be a builtin command, and the shell will call `/bin/echo`. This is insecure because the password will show up in the process table and can be seen with tools like `ps`.

In this case, you should use another scripting language. Here is an example in Perl:

#!/usr/bin/perl -w
open my $pipe, '|chpasswd' or die "can't open pipe: $!";
print {$pipe} "$username:$password";
close $pipe

Problem

I'm writing a shell script to automatically add a new user and update their password. I don't know how to get passwd to read from the shell script instead of interactively prompting me for the new password. My code is below. ``` adduser $1 passwd $1 $2 $2 ```

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