changing password using pexpect and passwd non-interactivly?

Question

I am trying to learn python to change users password non-interactively but nothing seems to be working.
pexepect module of python seems promising, so I am just trying to use it.
This tutorial is nice but it does not work.
There's lots of code on Internet regarding this but none of them seems to work.
And nor does my code:

#!/usr/bin/python
import pexpect
import time
def ChangePassword(user, pass):
    passwd = pexpect.spawn("/usr/bin/passwd %s" % user)

    for x in xrange(2):
        # wait for password: to come out of passwd's stdout
        passwd.expect("password: ")
        # send pass to passwd's stdin
        passwd.sendline(pass)
        time.sleep(0.1)

ChangePassword('rajesh', 'bar') # changes user "foo"'s password to "bar"

Error:

bash-3.00# ./solpas7.py
  File "./solpas7.py", line 4
    def ChangePassword(user, pass):
                                ^
SyntaxError: invalid syntax

EDIT : i changed pass to pa but not i am getting a lot and the password does not changes.

bash-3.00# ./solpas7.py
Traceback (most recent call last):
  File "./solpas7.py", line 14, in ?
    ChangePassword('rajesh', 'bar') # changes user "foo"'s password to "bar"
  File "./solpas7.py", line 9, in ChangePassword
    passwd.expect("password: ")
  File "/usr/lib/python2.4/site-packages/pexpect.py", line 1311, in expect
    return self.expect_list(compiled_pattern_list, timeout, searchwindowsize)
  File "/usr/lib/python2.4/site-packages/pexpect.py", line 1325, in expect_list
    return self.expect_loop(searcher_re(pattern_list), timeout, searchwindowsize                                              )
  File "/usr/lib/python2.4/site-packages/pexpect.py", line 1409, in expect_loop
    raise TIMEOUT (str(e) + '\n' + str(self))
pexpect.TIMEOUT: Timeout exceeded in read_nonblocking().
<pexpect.spawn object at 0x80e306c>
version: 2.3 ($Revision: 399 $)
command: /usr/bin/passwd
args: ['/usr/bin/passwd', 'rajesh']
searcher: searcher_re:
    0: re.compile("password: ")
buffer (last 100 chars): New Password:
before (last 100 chars): New Password:
after: pexpect.TIMEOUT
match: None
match_index: None
exitstatus: None
flag_eof: False
pid: 4683
child_fd: 3
closed: False
timeout: 30
delimiter: pexpect.EOF
logfile: None
logfile_read: None
logfile_send: None
maxread: 2000
ignorecase: False
searchwindowsize: None
delaybeforesend: 0.05
delayafterclose: 0.1
delayafterterminate: 0.1

Answer 1

You can't use pass as a variable name. It's a reserved keyword.

Edit: pexpect is waiting for the string "password: " but as you can tell from the error message passwd outputs "New Password: " (note the capital p) on your system.

buffer (last 100 chars): New Password:
before (last 100 chars): New Password:

Instead of passwd.expect("password: ") you need to use passwd.expect("Password: ") .

Answer 2

您还可以使用此选项使搜索不区分大小写：

passwd.expect('(?i)password:')