Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Hầu hết các hệ điều hành hiện đại làm việc với các tài khoản người dùng để cấp quyền truy cập vào hệ thống, và Ubuntu không là ngoại lệ. Bạn có thể không chú ý này, nếu trong quá trình cài đặt hoặc khi bạn cá nhân hoá hệ thống của bạn, bạn chọn tùy chọn để cho phép đăng nhập tự động, bạn được đưa trực tiếp vào máy tính để bàn của bạn khi bạn khởi động máy tính của bạn,. | C H A P T E R 21 Understanding Linux Users and File Permissions Most modern operating systems work with user accounts to grant people access to the system and Ubuntu is no exception. You might not have noticed this if during installation or when you personalized your system you selected the option to allow automatic logins you are taken directly to your desktop when you boot your PC thus masking the fact that a user is actually logging into the system. So whether you re aware of it or not you always have a user account inside Ubuntu. Your user account will have a defined set of attributes that will distinguish it from other user accounts for example a name and a Home folder. But it also will be a member of a group. Being a member of certain groups allows access to portions of the system that would be otherwise hidden because groups can enable permissions to access and manipulate files on your hard disks. And since all configuration in Ubuntu is stored in files see Chapter 10 those permissions will allow it to change the system itself. Understanding User and Group Accounts We ve already stated that to interact with Ubuntu you need a user account. However there s more to the story than that. For example there are situations in which you might need more than one user account. Either in the office or at home there may be more than one person that uses the computer and you surely will want to keep your personal configuration and data separate from theirs. That s when the need for additional user accounts arises. This section will explain what a user account is how to create it and how to work with groups. Users and Groups Each person who wishes to log into Ubuntu must have a user account. This will define what that user can and cannot do on the system with specific reference to files and folders. Because Ubuntu is effectively one large file system even hardware devices are files see Chapter 10 user permissions lie at the heart of controlling the entire system. They can
