TAILIEUCHUNG - Chapter-10-File systems and devices

One of the most revolutionary concepts of the UNIX operating system was its file system, the way in which it stores data. Although most other operating systems have copied it since then, including Microsoft’s platforms, none have come close to the elegance with which it is implemented. Many aspects of the file system are not immediately obvious, some of them not even to seasoned UNIX users. | 2 April 2003 17 00 47 The Complete FreeBSD page 181 In this chapter File permissions Mandatory Access Control Links Directory hierarchy File system types Mounting file systems FreeBSD devices Virtual terminals 10 File systems and devices One of the most revolutionary concepts of the UNIX operating system was its file system the way in which it stores data. Although most other operating systems have copied it since then including Microsoft s platforms none have come close to the elegance with which it is implemented. Many aspects of the file system are not immediately obvious some of them not even to seasoned UNIX users. We ve already looked at file naming conventions on page 125. In the next section we ll look at the file system access structure and hierarchy and on page 195 we ll look at how the file system treats hardware devices as files. File permissions A UNIX system may potentially be used by many people so UNIX includes a method of protecting data from access by unauthorized persons. Every file has three items of information associated with it that describe who can access it in what manner The file owner the user ID of the person who owns the file. The file group the group ID of the group that owns the file. A list of what the owner the group and other people can do with the file. The possible actions are reading writing or executing. v 2003 04 02 06 43 57 181 2 April 2003 17 00 47 The Complete FreeBSD . tools page 182 File permissions 182 For example you might have a program that accesses private data and you want to be sure that only you can execute it. You do this by setting the permissions so that only the owner can execute it. Or you might have a text document in development and you want to be sure that you are the only person who can change it. On the other hand the people who work with you have a need to be able to refer to the document. You set the permissions so that only the owner can write it that the owner and

TỪ KHÓA LIÊN QUAN
TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.