Running Mac OS X Tiger

Managing Users

Traditional Unix systems typically store their user and group information in the /etc/passwd and /etc/group files—and if you go looking, you can find these files on your Mac. However, after Mac OS X boots, it does not use these files. Instead, it uses Open Directory (discussed in Chapter 7) to store its user and group information. This allows the system to work equally well in home setups where there is only one machine and in enterprise environments where there might be hundreds of machines that use a central server for authentication.

While there are many ways to manage users on Mac OS X, the simplest and most direct by far is to use the Accounts preference panel.

Managing Users from the Command Line

Many hardcore Unix users are used to being able to manage users from the command line using tools like useradd ,usermod ,userdel ,groupadd ,groupmod ,groupdel ,gpasswd ,grpconv , and grpunconv. Unfortunately, these commands don’t exist on Mac OS X. The only tool of this kind on Mac OS X is the passwd command, which is used to change a user’s password.

While it is possible to perform some user management from the command line through direct manipulation of the NetInfo database using the niutil command (covered in Chapter 7), several pieces of data in a user’s NetInfo record, such as the generateduid property, don’t have command-line tools to manage them. For almost all purposes, and unless you really need to manage users from the command line, you should use the Accounts ...