毕业设计__mini shell的实现—.doc

毕业设计(论文) 题目: Mini Shell 的实现学生姓名学号 201022030121 班级计算机 102201H 所属院(系) 计算机科学与技术系指导教师 2014 年5月 20日 I Mini Shell 的实现摘要随着 linux 系统的普及,越来越多的人在更深入地研究 linux ,而对于微型 linux shel l 的研究是研究 linux 的重点。本文对 shell 的研究包括对其功能的了解,并实现对 shell 的列表、管道、输入重定向、输出重定向等命令功能,可以比较全面地认识 shell 解释器,并在 shell 中执行正确的命令,从而对它的功能、语法等在程序设计中必须用到的知识有了较为清晰的认识,最后通过对各个功能模块的具体分析,编写出正确实现各个功能的代码,从而完成一个简易的 shell 解释器的模拟。而且,在嵌入式领域中,硬件资源是有限的,但是需求是无限的。这就意味着们要利用有限的资源来完成各种各样的需求,而嵌入式设计和在传统的 PC 上编程是有很大差异的,它往往只需要一个庞大程序的很小的一部分就可以满足它的需求,所以我们不得不把一些无用的程序裁剪掉来换取空间。在嵌入式领域中像传统的 K shell , C shell , Bourne Shel l 等大型的 shell 程序就会使我们的硬件资源捉襟见肘。所以我们要有一个更适合嵌入式系统中使用的 shell ,这也是我本次设计的另一个目的。关键词: Shell ;程序;设计与实现;嵌入式 II Mini Shell ’s implementation Abstract panied by the popularize of the linux, more and more people are doing deeply study in it. The study of the shell in linux is the most important thing when study the linux. And how to study? It mainly includes the understand of some knowledge and function of the micro linux shell. Through the study of the orders in shell like list, pipe, input redirect and output redirect, readers can have a thorough sense about the shell and learn to use these orders accurately in shell which play an important role in programming later. Code accurately and achieve a simple shell with the functions above after analyzing the details of every functions module. Moreover, in the embedded field, the hardware resources are limited, but demand is unlimited. This means they have to use limited resources to plish a variety of needs, and embedded design and programming in the traditional PC, is very different, and it often requires only a small part ofa large program on meet its needs, so we had to cut out a number of useless programs in exchange for space. In the embedded field, as the traditional K shell, C shell, Bourne Shell and other large-scale shell program will make our hardware resources are stretched. So we need a more suitable for embedded systems used in the shell, this is my another objective of this design