Red Flag asianux Server 3 System Management: command-line Operations (i)

Familiarity with the command line interface is significant for using and managing Linux operating systems, and this chapter describes the knowledge of shell operations in the Red Flag asianux Server 3 system.

1.1http://www.aliyun.com/zixun/aggregation/22929.html "> basic knowledge

The following knowledge of the Linux shell and files and directories is the basis for learning this chapter.

1.1.1 File naming

The maximum length of a file name under Linux can be 256 characters, usually by letters, numbers, "." (dot number), "_" (underline), and "-" (minus sign). The file name cannot contain a "/" symbol, because "/" represents the delimiter in the root directory or path (as in DOS, "\") in the Linux directory tree.

The Linux system supports wildcard characters in file names, as follows:

Asterisk (*): matches 0 or more characters;

Question mark (?): matches any one character;

[Ab1 F]: matches any character enumerated in the collection. In this case, the collection is a, B, 1, or any uppercase character from a to F;

1.1.2 Path

The path through which the operating system looks for files is called the path name. You can refer to the file name directly when using the files in the current directory, and you must indicate in which directory the file is in if you want to use a file in another directory.

Depending on the starting point of the lookup file, there are two paths: an absolute path and a relative path. The path starting at the root is called the absolute path, and the path starting from the current directory is called the relative path, and the relative path changes as the user's working directory changes.

As with DOS, each directory has a "." that represents the current directory. Files and ".." that represent the parent directory of the current directory. File, the relative pathname is generally from the "..." Started.

In the Linux directory tree, the delimiter in the root directory or path is "/".

1.1.3 File type

Red Flag asianux Server 3 system supports the following file types: Normal files, directory files, device files, and symbolic link files.

Ordinary files: Including text files, data files, executable binaries, and so on.

Directory files: Short directory, Linux in the directory as a special file, using it to form a hierarchical tree structure of the file system. Each directory file contains at least two files, "..." Represents the previous level of the directory, "." Represents the directory itself. Device files: A special file that Linux systems use to identify each device drive, and the core uses them to communicate with 11585.html "> hardware devices." There are two types of special equipment files: Character devices and block devices. Symbolic Links: A special file that holds data that is the path to a file in a file system. When using a symbolic link file, the system automatically accesses the saved path.