作者：华清远见嵌入式学院。《Linux设备驱动开发详解》（08&09年度畅销榜TOP50）第5章、Linux文件系统与设备文件系统。由于字符设备和块设备都很好地体现了“一切都是文件”的设计思想，掌握Linux文件系统、设备文件系统的知识非常重要。首先，设备驱动最终通过操作系统的文件系统调用或C库函数（本质也基于系统调用）被访问。其次，驱动工程师在设备驱动中不可避免地会与设备文件系统打交道，如Linux 2.4内核的devfs文件系统和Linux 2.6内核的基于sysfs的udev文件系统。5.1节讲解了通过Linux API和C库函数在用户空间进行Linux文件操作的编程方法。5.2节分析了Linux文件系统的目录结构，简单介绍了Linux内核中文件系统的实现，并给出了文件系统与设备驱动的关系。5.3节和5.4节分别讲解Linux 2.4内核的devfs和Linux 2.6内核所采用的udev设备文件系统，并分析了两者的区别。-Author: HuaQing vision embedded institute. The Linux device driver development "(08 and 09 sep TOP50) annual list of best-selling chapter 5, Linux file system and equipment file system. Because characters equipment and piece of equipment are properly shows "everything is a document" design ideas, master Linux file system, equipment of the knowledge of the file system is very important. First, the device driver finally through the operating system of the file system calls or C library function (nature based on system call) were interviewed. Second, drive engineer in device driver inevitably will and equipment file system, such as Linux 2.4 kernel dealing with the devfs file system and Linux 2.6 kernel based on the udev sysfs of file system. Section 5.1 explained through the Linux API and C library function in user space for Linux file operation of the programming method. Section 5.2 the Linux analysis