Specifications

Chapter 1 Web Technologies Overview 17
Dening Realms
When you dene a realm, which is typically a folder (or le system), the access
privileges you set for the realm apply to all contents of that folder. If a new realm is
dened for a folder in the existing realm, only the new realm privileges apply to that
folder and its contents. For information about creating realms and setting access
privileges, see “Using Realms to Control Access” on page 39.
Note: When an assigned user or group possesses fewer permissions than the
permissions assigned to user Everyone, that user or group is deleted upon a refresh.
This happens because the access assigned to Everyone preempts the access assigned
to specic users or groups with fewer permissions than those possessed by Everyone.
Greater permissions always take precedence. Consequently, the list of assigned
users and groups with fewer permissions are not saved in the Realms pane upon
refresh if their permissions are determined to be preempted by the permissions
assigned to Everyone.
After the refresh, the names are no longer listed in the list on the right in the Realms
pane. Also, for a brief period of time, user Everyone will switch its displayed name
to “no-user.”
Understanding Multipurpose Internet Mail Extension (MIME)
Multipurpose Internet Mail Extension (MIME) is an Internet standard for specifying
what happens when a web browser requests a le with specic characteristics. You
can choose the response you want the web server to make based on the le’s sux. Your
choices depend partly on what modules you have installed on your web server. Each
combination of a le sux and its associated response is known as a MIME type mapping.
MIME Suxes
A sux describes the type of data in a le. Here are some examples:
txt for text les Â
cgi for Common Gateway Interface les Â
gif for GIF (graphics) les Â
php for PHP: Hypertext Preprocessor (embedded HTML scripts) used for Webmail, Â
and so on
ti for TIFF (graphics) les Â
Mac OS X Server includes a default set of MIME type suxes. This set includes all the
suxes in the mime.types le distributed with Apache, with a few additions. If a sux
you need is not listed or does not have the behavior you want, use Server Admin to
add the sux to the set or to change its behavior.
Note: Do not add or change MIME suxes by editing conguration les.