Mini-shell脚本的开发.docVIP

毕业设计说明书 Mini--Shell 脚本的开发 学生姓名： 学号： 学 院： 系 名： 专 业： 指导教师： 2013年 5 月 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 shell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 Shell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Abstract Accompanied 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 accomplish a variety of needs, and embedded design and programming in the traditional PC, is very different, and it often requires only a small part of a 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 us