| In this chapter, we studied the critical components of the file system. Foremost are a file's inode on the disk and, once opened by the kernel, its vnode. These two incarnations of what is basically the same data define the credentials and attributes of all files in the HP-UX environment. Specialized files known as directories coupled with the kernel's VFS structures allow the creation of a seamless hierarchical directory structure that may incorporate files from a variety of local and remote file systems. A user or application needs no knowledge of the mount path specifics or file system types. We also discovered that there are several caches and hashing schemes implemented by the kernel to improve system performance levels. In the next chapter we build on the topics we have covered so far and look at the process/thread life cycle. |