Webopedia on Google+Webopedia on TwitterWebopedia on FacebookTech Bytes Blog
Main » TERM » T »

thunk

(v.) In PCs, to convert a 16-bit memory address to a 32-bit address, and vice versa. Thunking is necessary because Intel's older 16-bit microprocessors used an addressing scheme called segmented memory, whereas their 32-bit microprocessors use a flat address space . Windows 95 supports a thunk mechanism to enable 32-bit programs to call 16-bit DLLs. This is called a flat thunk.

On the other hand, 16-bit applications running under Windows 3.x and Windows for Workgroups cannot use 32-bit DLLs unless the 32-bit addresses are converted to 16-bit addresses. This is the function of Win32s, and is called a universal thunk.

According to folklore, the term thunk was coined by the developers of the Algol-60 programming language, who realized late one night that the data type of parameters could be known with a little forethought by the compiler. That is, by the time the compiler processed the parameters, it had already thought of (thunked) the data types. The meaning of the term has changed considerably in recent years.

(n.) The operation of converting between a segmented memory address space and a flat address space.







TECH RESOURCES FROM OUR PARTNERS
DID YOU KNOW?
5 Best Valentines Day Ideas for Open Source Romantics

Because nothing says "I Love You" Like an open source app. Read More »

Guarding your Data against Cyber Attacks

In this new era of heightened stakes comes an increased need for a comprehensive security strategy. Let's take a look at how cyber-threats have... Read More »

The Great Data Storage Debate: Is Tape Dead?

Tape clearly is on the decline. But remember, legacy systems can hang for a shockingly long time. Read More »

QUICK REFERENCE
Network Fundamentals Study Guide

A network is a group of two or more computer systems or devices, linked together to share resources, exchange files and electronic communications.... Read More »

Computer Architecture Study Guide

This Webopedia  study guide describes the different parts of a computer system and their relations. Read More »

Webopedia Polls

The trend for the past two years has been for shoppers to spend more online during the holiday season. How do you typically shop for holiday... Read More »