Specifications

314 Glossary
password policy A set of rules that regulate the composition and validity of a user’s
password.
Password Server See Open Directory Password Server.
pathname The location of an item within a file system, represented as a series of
names separated by slashes (/).
PDC Primary domain controller. In Windows networking, a domain controller that has
been designated as the primary authentication server for its domain.
permissions Settings that define the kind of access users have to shared items in a file
system. You can assign four types of permissions to a share point, folder, or file: Read &
Write, Read Only, Write Only, and No Access. See also privileges.
PHP PHP Hypertext Preprocessor (originally Personal Home Page). A scripting
language embedded in HTML that’s used to create dynamic webpages.
physical disk An actual, mechanical disk. Compare with logical disk.
PID Process ID. A number assigned to a UNIX process when it starts. The PID allows you
to refer to the process at a later time.
POP Post Office Protocol. A protocol for retrieving incoming mail. After a user retrieves
POP mail, it’s stored on the user’s computer and is usually deleted automatically from
the mail server.
port A sort of virtual mail slot. A server uses port numbers to determine which
application should receive data packets. Firewalls use port numbers to determine
whether data packets are allowed to traverse a local network. “Port” usually refers to
either a TCP or UDP port.
port name A unique identifier assigned to a Fibre Channel port.
portable home directory A portable home directory provides a user with both a local
and network home folder. The contents of these two home folders, as well as the user’s
directory and authentication information, can be automatically kept in sync.
POSIX Portable Operating System Interface for UNIX. A family of open system
standards based on UNIX, which allows applications to be written to a single target
environment in which they can run unchanged on a variety of systems.
Post Office Protocol See POP.
Postscript Printer Description file See PPD file.