Managing users and groups
It is also common to need to add or modify users and groups to our filesystem. This recipe explains how it is done.
The user information is stored in the
/etc/passwd file, a text file that is used as a database for the system user's information. The
passwd file is human-readable.
Each line on it corresponds to one user in the system, and it has the following format:
<username>:<password>:<uid>:<gid>:<comment>:<home directory>:<login shell>
Let's see each of the parameters of this format:
username: A unique string that identifies the user at login
uid: User ID, a number that Linux uses to identify the user
gid: Group ID, a number that Linux uses to identify the user's primary group
comment: Comma-separated values ...