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Newsletter - Issue 1 |
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DLL Files - by B0blet -
Level = Beginners As you may know, this is my first article for UltrA. This month we will focus on windows DLL's, Where the basics will be explained. If you are new to windows programming, reading this article should be rewarding as it covers the basic concept of windows DLL's. This month's article takes a question/answer approach, most people find this less confusing and easier to understand. If you have any comments, please post in the forum in the DLL section. Now, let's get started. 1. What exactly IS a DLL? "DLL" is an acronym for "Dynamic Link Library". Programmers use DLL's to store useful functions and resources for their programs in a separate file (*.dll). A DLL is NOT a program, it is usually a PART of one or more programs. The program(s) may call functions from the DLL. A DLL is not limited no a specific program or programming language. For example, a function in a DLL written in C can be called from a Liberty Basic application. If you have ever worked with the Windows API, you have used DLL's! Windows API calls are simply functions contained in DLL's. These DLL's come with windows and are present on most windows systems. As a matter of fact, "Windows programming" is all about calling these functions from the DLL's . Most of the functions in the windows DLL's that are a part of the windows API are written in C/C++. Liberty basic is capable of loading any DLL and calling exported functions easily, this gives it great potential for windows programming. 2. Why do we need DLL's? Microsoft Windows do not release the source code like Linux, so programmers cannot modify and access the source code freely. However, Microsoft want developers to program software for their operating system - therefore they have provided an API (Application Programming Interface). The API consists of DLL files which contain compiled functions that can be used to interact with the Operating System through your own code. For example, if you wanted your program to be capable of shutting down the user's computer - you would have to call the appropriate function to do so. Once the function is called from your program it will return a result and then proceed to shut down. 3. Are DLL's hard to use with Liberty Basic? No, Liberty basic provides great DLL support. A simple example will be included in next month's article. 4. Can I write my own DLL's? Yes. You can store all your favourite, commonly used functions and use it in all your projects. Easy and Powerful. You can write your DLL's in any windows programming language. 5. Can other programmers use my DLL's? Yes. If you provide the programmers with documentation, explaining how to use the functions in your DLL. Next issue I will show you how to compile your own project using some API calls and your own DLL. B0blet - (Antrix2002@hotmail.com) |
