WHAT IS A DOS EXTENDER?

Unknown · March 1999

Unknown · March 1999

: WHAT IS A DOS EXTENDER?

A Dos extender is a program that allows you to run

code in Protected Mode, usually providing a variety

of services to help your program call real-mode interrupts,

allocate memory, and provide virtual memory.

Under Real (or v86) mode, you can only execute code in

in the lower 640 KB of memory, regardless of how much memory

is installed. Dos Extenders take care of the complex memory

addressing involved in Protected Mode, and allow you to allocate

and use all the available memory. Typically, the also take

care of selectors and such, allowing you to use simple flat

pointers.

Generally, if you want to use the features of your 386+ comp,

and aren't a master of Protected Mode, extenders are what you want.

While the term "DOS extender" generally refers to DOS progs with

PMODE/W 1.33 or some other extender, all windows programs acutally

use a DOS extender, know as DOSX.

Matthew Gross

URL:http://acheronx.resnet.tamu.edu

Unknown · April 1999

: : WHAT IS A DOS EXTENDER?

: A Dos extender is a program that allows you to run

: code in Protected Mode, usually providing a variety

: of services to help your program call real-mode interrupts,

: allocate memory, and provide virtual memory.

: Under Real (or v86) mode, you can only execute code in

: in the lower 640 KB of memory, regardless of how much memory

: is installed. Dos Extenders take care of the complex memory

: addressing involved in Protected Mode, and allow you to allocate

: and use all the available memory. Typically, the also take

: care of selectors and such, allowing you to use simple flat

: pointers.

: Generally, if you want to use the features of your 386+ comp,

: and aren't a master of Protected Mode, extenders are what you want.

: While the term "DOS extender" generally refers to DOS progs with

: PMODE/W 1.33 or some other extender, all windows programs acutally

: use a DOS extender, know as DOSX.