O'Reilly logo

Running Mac OS X Tiger by James Duncan Davidson, Jason Deraleau

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Nonhuman Users

Even if you are the only human user of the system, there are well over a dozen accounts on the system. Most of these user accounts are not intended for use by you or any user on the system but are set up for use by various services and programs on the system. These nonhuman accounts let applications, such as the Apache web server and the Postfix mail server, run in a controlled environment so if they are breached by a hacker, the potential damage is limited. Table 6-1 lists some of the nonhuman users that are defined on the system.

Table 6-1. Some of Mac OS X’s nonhuman users

Username

User ID

Description

root

0

The administrative user

daemon

1

Core system daemons

lp

26

Printing service

postfix

27

The Postfix SMTP server

www

70

The Apache web server

nobody

99

A user with greatly restricted access

Many of the nonhuman users, such as cyrusimap and qtss, aren’t used on the average person’s system but instead are defined for use on Mac OS X Server. Others, such as postfix and www, are used only when you run the Postfix mail server or the Apache web server. Under most conditions, you’ll notice only processes owned by either your own ID or by the root user when viewing processes in the Activity Monitor or with the ps command.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required