目 录摘 要 1前言 21 绪论 31.1 Shell 的定义.............................................................................31.1.1 UNIX Shell......................................................................31.2 shell 的历史..............................................................................41.3 shell 的职责..............................................................................42 开发环境和开发工具介绍 62.1 开发环境--Ubuntu.....................................................................62.2 开发工具-GCC...........................................................................63 模拟 shell 设计 73.1 简单 shell 设计思想....................................................................73.2 复杂 shell 设计思想....................................................................83.2.1 作业与作业前后调度实现方法..............................................83.2.2 进程组、会话与终端...........................................................93.2.3 命令行............................................................................103.2.4 &、bg、fg 等信号的思想.................................................103.2.5 管道..............................................................................113.2.6 重定向............................................................................114 Shell 的实现 134.1 数据结构...........................................................................134.2 程序结构...........................................................................134.2.1 初始化环境.....................................................................134.2.2 解析命令........................................................................144.2.3 查找外部程序..................................................................154.2.4 执行命令........................................................................164.2.5 管道................................................................................