problem with PIPE

[Felix Benner]

Dhika Cikul schrieb:
> Hello,
> 
> I'm new in Python, i don't know my subject is correct or wrong. I have
> problem with my script. I want to change password with passwd password
> in python without user submitted anything from keyboard. I get
> tutorial that i must use pipe to process this. And this is my code :
> 
> [code]
> 
>   1.
>   2. #!/usr/bin/python
>   3.
>   4. import os
>   5.
>   6. COMMAND = 'passwd'
>   7. PASSWD  = 'mypassword'
>   8.
>   9. # open a pipe to passwd program and
>  10. # write the data to the pipe
>  11. p = os.popen("%s" % COMMAND, 'w')
>  12. p.write(PASSWD)
>  13. p.write('\n')
>  14. p.write(PASSWD)
>  15. p.close()
>  16.
> [/code]
> 
> 
> but i got this error :
> 
> [output]
>    [cp at server cp]$ ./password
>    Changing password for user cp.
>    Changing password for cp
>    (current) UNIX password: passwd: Authentication token manipulation error
> [/output]
> 
> Anyone can help me how to write to pipe.. i try several method, and
> always fail.
> 
> Thank's

I guess the passwd program doesn't allow changing passwords from a pipe
since it is a potential security hole.