CHAPTER 14 UNDERSTANDING LINUX FILES AND (Freelance web design) USERS
CHAPTER 14 UNDERSTANDING LINUX FILES AND USERS 221 The -l option tells the ls command to list nearly all the details about the files. If you do this in GNOME Terminal, you ll see that the listing is color-coded. Table 14-1 shows what each color indicates. The command returns a lot of additional information, including who owns which file and what you and others can do with it. This requires an understanding of users and file permissions, which we ll discuss next. Tip The command ls -la will give you even more information perhaps too much for general use. In most instances, ls -l should show enough information. Table 14-1. Color-Coding Within GNOME Terminal Color Type of File Black text Standard file Light-blue text Directory Black outline with yellow text Virtual device1 Green text Program or script2 Cyan text Symbolic link to another file3 Pink text Image file Red text Archive4 1 This is found only in the /dev directory. 2 Technically speaking, green text indicates a program or script that has merely been marked as being executable. 3 This is similar to a Windows desktop shortcut. 4 Installation files are also marked red because they re usually contained in archives. Users and File Permissions The concept of users and permissions is as important to Ubuntu as the idea of a central and all- encompassing file system. In fact, the two are implicitly linked. When initially installing Linux, you should have created at least one user account. By now, this will have formed the day-to-day login that you use to access Linux and run programs. Although you might not realize it, as a user, you also belong to a group. In fact, every user on the system belongs to a group. Under Ubuntu, ordinary users belong to a group based on their username (under other versions of Linux, you might find that you belong to a group called users).