alias

1. operating system A name, usually short and easy to

remember and type, that is translated into another name or

string, usually long and difficult to remember or type. Most

command interpreters (e.g. Unix's csh) allow the user to

define aliases for commands, e.g. "alias l ls -al". These are

loaded into memory when the interpreter starts and are

expanded without needing to refer to any file.

2. networking One of several alternative hostnames with

the same Internet address. E.g. in the Unix hosts

database (/etc/hosts or NIS map) the first field on a line

is the Internet address, the next is the official hostname

(the "canonical name" or "CNAME"), and any others are

aliases.

Hostname aliases often indicate that the host with that alias

provides a particular network service such as archie,

finger, FTP, or World-Wide Web. The assignment of

services to computers can then be changed simply by moving an

alias (e.g. www.doc.ic.ac.uk) from one Internet address to

another, without the clients needing to be aware of the

change.

3. file system The name used by Apple computer, Inc. for

symbolic links when they added them to the System 7

operating system in 1991.

(1997-10-22)