More links, and a word about drivers

摘要

In last month's column, we saw how file links work in Unix, and I explained the two distinct types of link: soft (also known as symbolic) and hard. Links are frequently used and are convenient for a number of things. A long directory path can be shortened to something simpler; files can effectively be copied around the filesystem without having to duplicate the data. Also, when directory structures change, it's useful to provide a link for backward compatibility - /usr/doc, for example, used to contain application documentation, but the standards now say this sort of information should be under /usr/share/doc, so you may well find a symbolic link from the former to the latter.