I am looking into ways that my script (run as a non-privelaged) can determin whether or not a user on the system exists. I have come up with the following ideas:
1. Check in /etc/passwd for the account*
2. Check to see if a homedir exists using getpwnam.
3. Use A Text File To Log Users Added*
I have got 2. working, but i am looking for a better solution. I like the idea of a text file, because then i can manualy add usernames that are not on my system (as a kind of blacklist). The only worry i have, is that this system is goign to have around 5-6000 users, so i'm not sure if this solution will be slow.