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System programming (or systems programming) is the activity of programming computer system software. The primary distinguishing characteristic of systems programming when compared to application programming is that application programming aims to produce software which provides services to the user (e.g. word processor), whereas systems programming aims to produce software which provides services to the computer hardware (e.g. disk defragmenter). It requires a greater degree of hardware awareness. == Overview == The following attributes characterize systems programming: * The programmer will make assumptions about the hardware and other properties of the system that the program runs on, and will often exploit those properties, for example by using an algorithm that is known to be efficient when used with specific hardware. * Usually a low-level programming language or programming language dialect is used that: * * can operate in resource-constrained environments * * is very efficient and has little runtime overhead * * has a small runtime library, or none at all * * allows for direct and "raw" control over memory access and control flow * * lets the programmer write parts of the program directly in assembly language * Often systems programs cannot be run in a debugger. Running the program in a simulated environment can sometimes be used to reduce this problem. Systems programming is sufficiently different from application programming that programmers tend to specialize in one or the other. In system programming, often limited programming facilities are available. The use of automatic garbage collection is not common and debugging is sometimes hard to do. The runtime library, if available at all, is usually far less powerful, and does less error checking. Because of those limitations, monitoring and logging are often used; operating systems may have extremely elaborate logging subsystems. Implementing certain parts in operating systems and networking requires systems programming, for example implementing Paging (Virtual Memory) or a device driver for an operating system. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「System programming」の詳細全文を読む スポンサード リンク
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