Shell Programming and Scripting

We have a business need to modify the /etc/passwd file every time a new user gets added, because the user ID begins with a zero. When you create the new user in smit, even if you put the leading zero in, it does not retain it when the entry is added.

That being said, I need to create a script that will take an argument (the username) and append the zero to the beginning of the user ID field.

Anyone have any suggestions?

Thanks in advance!

I should note, from man useradd:

Code:

CAVEATS
...

       Usernames must start with a lower case letter or an underscore,
       followed by lower case letters, digits, underscores, or dashes. They
       can end with a dollar sign. In regular expression terms:
       [a-z_][a-z0-9_-]*[$]?

So it's not just smit that disallows these usernames, it's a general login requirement. If you force /etc/passwd to contain these entries it may misbehave, violate it at your own risk.

You should be able to get away with _0username if that will work for your purposes.

Do you have usermod available? You can do usermod -l _0username username to avoid the peril of editing /etc/passwd yourself.

its no the username, but the uid that needs to be appended with a zero. This is because our LDAP configuration requires that the uid in unix match the uid in the LDAP tree and our business uses leading zeros in LDAP. I have an idea and am working on it but anything else you think of would be great.

---------- Post updated at 04:16 PM ---------- Previous update was at 04:16 PM ----------

bah, this is aix 6.1 if that helps

I've never seen leading zeroes in a UID or GID and can't predict the potential side-effects of adding them. They might go away of their own accord any time you edit that user again, for that matter. They're not supposed to be strings and won't be processed as such. Hopefully most things will just ignore them but that's no guarantee.

Are you absolutely sure there's absolutely no way to just have them exported with a leading zero as far as your NIS config is concerned or something? Hand-butchering your /etc/passwd file should be an absolute last resort.

This is a process that I inherited from years of doing it this way. the departments here are so separated, reverse engineering this whole thing would be a nightmare. I agree that hand modifying the passwd file is ridiculous but im not sure working to change this process would get me far. Appending the zero has not caused any ill results over the years until today when someone with sudo privileges accidentally deleted the root line, effectively breaking the whole system. A few hours later and we are back, now we need to limit who touches it, hence the need for a script.

I have something in the works.

I'm lost here. If you're using LDAP why are the users in /etc/passwd?

our application spawns unix shell processes and it is not LDAP authenticated so it still uses the passwd file. band aid after band aid after band aid and you get the world I've inherited