EGA (enhanced graphics adapter):A video adapter capable of displaying all the modes of the color graphics adapter (CGA) plus additional modes in medium resolution in up to 64 colors.
EMM386.EXE:An example of a VCPI server. EMM386.EXE simulates expanded memory in extended memory for an 80386 or higher processor.
EMS:Expanded Memory Specification. See “expanded memory.”
emulator:A floating-point math package that provides software emulation of the operations of a math processor.
environment strings:A series of user-definable and program-definable strings associated with each process. The initial values of environment strings are established by a process's parent.
environment table:The memory area, defined by the operating system, that stores environment variables and their values.
environment variable:A string associated with an identifier and stored by the operating system. Environment variables are defined by the SET command. The identifier and the string associated with it can be used by a program.
.ERR:The extension for a file of error-message text or error output.
error code:See “exit code.”
escape sequence:A specific combination of an escape character (often a backslash) followed by a character, keyword, or code. Escape sequences often represent white space, nongraphic characters, or literal delimiters within strings and character constants.
.EXE:One of the extensions for an executable file, which is a file that can be loaded and executed by the operating system.
executable file:A program ready to be run by an operating system, usually with one of the extensions .EXE, .COM, or .BAT. When the name of the file is typed at the system prompt, the statements in the file are executed.
exit code:An integer returned by a program to the operating system or the program's caller after completion to indicate the success, failure, or status of the program. Also called a return code or error code. :Exit code also refers to the executable code that a compiler places in every program to terminate execution of the program. This code typically closes open files and performs other housekeeping chores. When a program terminates in CodeView, the current line is in the exit code. No source code is shown since none is available. See also “startup code.”
expanded memory:Memory above 640K made available to real-mode programs and controlled through paging by an expanded memory manager.
expanded memory emulator:A device driver that allows extended memory on computers with an 80286 or later processor to behave like expanded memory.
expanded memory manager (EMM):A device driver for controlling expanded memory.
explicit allocation:Assignment to a segment at compile time.
expression:A combination of operands and operators that yields a single value.
extended ASCII:ASCII codes between 128 and 255. The meanings of extended ASCII codes differ depending on the system.
extended dictionary:A summary of the definitions contained in all modules of a standard library. LINK uses extended dictionaries to search libraries faster.
extended memory:Memory above either 640K or 1 megabyte made available to protected-mode programs on computers with an 80286 or later processor. Extended memory is used by Windows in standard mode or 386 enhanced mode.
extended memory manager:A device driver for controlling extended memory, for example, HIMEM.SYS for Windows.
extender-ready:See “DOS-extended.”
extension:One, two, or three characters that appear after a period (.) following the base name in a filename. For example, .TXT is the extension of the filename README.TXT. A filename does not necessarily have an extension. Sometimes the extension is considered to include the preceding period.
external reference:A routine or data item declared in one module and referenced in another.