Dynamic link library - database applications, Visual Basic Programming


The dynamic link library (dll) permits one copy of a function to be shared among some parallel executing programs. The dll is a file that contains a number of modules. The function in a dll is connected to a program which uses it when the application is run. Every time the program executes the dll is connected to the program.

The dynamic-link library (DLL) is a module which contains functions and data that can be used by the other module.

The DLL can define 2 kinds of functions: Internal and Exported.

Exported : The exported functions are intended to be called by the other modules, as well as from within the DLL where they are defined.

Internal : The Functions are normally intended to be called only from within the DLL where they are defined. Though a DLL can export data, its data is normally used only by its functions. Though, there is nothing to prevent the other module from reading or writing that address.

The DLLs provide a way to modularize applications so that the functionality can be updated and reused more easily. They also help to reduce memory overhead when some applications use the same functionality at the same time, as though each application gets its own copy of the data, from which they can share the code.

The API (Windows application programming interface) is implemented as a set of the dynamiclink libraries, therefore any process which uses the Windows API uses the dynamic linking.

  •  About Dynamic-Link Libraries
  •  Using Dynamic-Link Libraries
  •  Dynamic-Link Library Reference

Even though the DLLs and applications are both executable program modules, they vary in some ways. To the end-user, the most obvious difference is that the DLLs are not programs which can be directly executed. There are 2 primary differences from the system's point of view between the applications and DLLs:

An application can have multiple illustration of itself running in the system concurrently, while a DLL can have only one instance.

An application can own things like a global memory stack, file handles, and a message queue, whereas DLL cannot.

Posted Date: 10/10/2012 2:42:28 AM | Location : United States

Related Discussions:- Dynamic link library - database applications, Assignment Help, Ask Question on Dynamic link library - database applications, Get Answer, Expert's Help, Dynamic link library - database applications Discussions

Write discussion on Dynamic link library - database applications
Your posts are moderated
Related Questions
Assume that s is a string variable that is supposed to contain a value to be converted to integer. Write a fragment of code that converts the value to integer variable and displ

ILLUSTRATION OF CCOLORDIALOG The constructor of the CColorDialog takes the initial parameter as the default color and the next parameter specifies how much the dialog is displa

You can employ Do...Loop statements to run a block of statements indefinite number of times. The statements are repeated either whilst a condition is True or till a condition becom

'This program compares interest rates between two banks and determines the best bank PublicClassForm1 PrivateSub Button1_Click(sender AsSystem.Object, e AsSystem.EventArgs) H

Methods: VBScript Dictionary Object Method D escription Add Method Adds a key, item pair. Exists Method

Coding conventions are recommended that may help you write code via Microsoft Visual Basic Scripting Edition. Coding conventions can include the given: Naming conventions for ob

Events: The Controls are placed on a form and then to make them functional an "event procedure" is related with the control object. An event process is what happens in respons

Just like normal objects Dictionary object also has definite properties. These properties can be set to any valid value & can be retrieved as and while required. Pr

John''s gas supply is read from a 4-digit meter each month that shows the current total gas used in cubic meters. The amount of gas used that month is determined by subtracting t

A triangle is equilateral if all three sides are equal, isosceles if any two (but no more than two) sides are equal, and scalene if no two sides are equal. A triangle will be input