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Date: Tue, 16 Aug 2011 17:56:37 +0200
From: Alexander Kapps <alex.kapps@web.de>
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To: python-list@python.org
Subject: Re: Linux : create a user if not exists
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On 16.08.2011 16:57, smain kahlouch wrote:
> Ok than you. You're right but it doesn't help me :
> I replaced it :
>
>  >>> def finduser(user):
> ...     if pwd.getpwnam(user):
> ...             print user, "user exists"
> ...             return True
> ...     return False
> ...
>  >>> finduser('realuser')
> realuser user exists
> True
>  >>> finduser('blabla')
> Traceback (most recent call last):
>    File "<stdin>", line 1, in ?
>    File "<stdin>", line 2, in finduser
> KeyError: 'getpwnam(): name not found: blabla'


Untested:

def finduser(name):
     try:
         return pwd.getpwnam(name)
     except KeyError:
         return None

if not finduser("myuser"):
     print "creating user..."
else:
     print "user already exists"


Has the advantage that finduser() returns the user details if needed.


(BTW: Please don't top-post)