E vocabularies

By admin, 29 May, 2024

ed editor
A line-oriented program for modifying the contents of text files. The program 
operates by accepting commands from the user; for example, issuing the 
command s/Unix/UNIX/g would cause the editor to replace each instance of the 
string "Unix" on the current line with "UNIX." 
A program for modifying the contents of text files. Full-screen editors, such as vi,
use video display terminals to display several lines of the file being manipulated; 
they allow the user to move the cursor to a specific location and change the text 
there. Line editors, such as ed, work on a line-by-line basis. Stream editors, such 
as sed, work by applying commands from a previously prepared list (called a 
script) instead of by accepting commands from the user. 
effective root directory
The point where a system starts when searching for a file. Its pathname begins 
with a slash (/). 
effective user ID
The current user ID, but not necessarily the user's ID. For example, a user logged 
in under a login ID may change to another user's ID. The ID to which the user 
changes becomes the effective user ID until the user switches back to the original
login ID. 
EGP (External Gateway Protocol)
A type of routing protocol that allows individual networks to communicate with 
the Internet backbone. 
See also Internet
A text editor developed by the Free Software Foundation that is available for all 
UNIX systems, although it is not a standard part of Berkeley UNIX or System V. It 
is included with the DIGITAL UNIX operating system. 
The set of conditions under which a user is working on the computer. The 
environment includes such information as the name of the working directory, the 
name of the command interpreter, the identity of the user's terminal, and so on. 
environment variable
A symbol containing information that can be used by shells or commands. 
Environment variables are available to all processes in a given process group; 
they are propagated by the creation of a child process. 
See also process variable
EOF (end of file)
1. A condition indicating that the end of a data file has been reached by a 
program reading the file. 
2. A specific sequence of characters written on a magnetic tape. 
See also BOM, file mark
equivalence class
A grouping of characters or character strings that are considered equal for 
purposes of collation. For example, many languages place an uppercase 
character in the same equivalence class as its lowercase form, but some 
languages distinguish between accented and unaccented character forms for the 
purpose of collation. 
Any condition in which the expected results of an operation are not achieved. In 
XTI, an indicator that is returned by a function when it encounters a system or 
library error in the process of executing. The object is to allow applications to take
an action based on the returned error code. 
1. To protect a character from interpretation by a program by preceding it with a 
backslash (\). 
2. An ASCII character that is usually interpreted as a command to cease a certain 
activity or as the initial character of a sequence that performs a special function. 
Cursor control sequences for many terminals and workstations use the escape 
See also quote
A catchall directory, which usually contains miscellaneous system data files (such 
as termcap, the terminal capabilities database). 
A communications concept for local communication networks that interconnects 
different kinds of computers, information processing products, and office 
equipment. It is a 10-megabit-per-second baseband local area network (LAN) 
using carrier sense multiple access with collision detection (CSMA/CD). The 
network allows multiple stations to access the medium at will without prior 
coordination, and avoids contention by using carrier sense and deference, and 
detection and transmission. 
See also expedited data, out-of-band data
Expedited Transport Service Data Unit
An occurrence, or happening, that is significant to a transport user. Events are 
asynchronous, in that they do not happen as a result of an action taken by the 
event executable image
An executable image located in physical memory. 
event management
A mechanism by which transport providers notify transport users of the 
occurrence of significant events. 
executable file
A data file created by a compiler that contains program information a computer 
can read, interpret, and execute. Also called an image or a binary file. 
ex editor
A line-oriented program for modifying the contents of text files. The ex editor is 
an extended version of the ed editor. 
expedited data
Data that is considered urgent. The semantics of this data are defined by the 
transport provider. 
See also out-of-band data
1. A representation of a value; for example, variables and constants appearing 
alone or in combination with operators. 
2. In programming languages, a language construct for computing a value from 
one or more operands, such as literals, identifiers, array references, and function 
3. A configuration of signs. 
extended character
A character other than a 7-bit ASCII character. An extended character can be a 1-
byte code point with the eighth bit set (ordinal 128-255). 
External Gateway Protocol
See EGP (External Gateway Protocol)