Information Security system Design Foundation Nineth Week study Summary

(1) LS

Used to display the details of a file (user name, group name, size, creation time, read and write execution rights). ）

(2) Who

How do I view the currently logged in user?

-who am I

How do I list the logged in user?

-who OR-W

(3) FileInfo display file information

To implement the display file information, a stat data structure is established.

To determine if the command has operands first

(4) SPWD list current directory

(5) The mkdir command is used to create a new directory. This new directory can be used not only for absolute paths, but also for relative paths. However, the user creates a new directory with the assumption that the creator should have write permission to the parent directory of the new directory being created.

How do I create a parent directory first if its parent directory does not exist?

-mkdir-p

How do I specify permissions for this directory while creating a new directory?

-mkdir-m

(6) The rmdir command function is used to delete the specified empty directory. after all files and subdirectories in the directory are deleted, the directory can be deleted using the rmdir command. When a user deletes a directory, the parent directory of the directory should have write permissions.

How do I delete all directories on the specified path (more than one directory)?

-rmdir-p

(7) Setecho设置回显位的状态，命令行参数为y则开启，否则关闭。

Echostate读取驱动设置并显示回显位的状态。

(8) file Operation command

cat：由第一行显示文件内容<br>-cat-n l显示行号

more： 一页一页显示，可翻页查看

less： 与more类似，可以往前翻页

(9) CD command

The CD enters the user's home directory;
CD ~ Enter the user's home directory;
CD-Returns the directory where the directory was before it was entered;
Return to the parent directory (if the current directory is "/", then "/"; "..." after execution) The meaning of the parent directory);
Cd.. /.. Return to the top level two directory;
CD!$ Use the parameters of the previous command as CD parameters.

Problems encountered

1. What is the difference between the Linux command LS and-ls?

Commands in Linux do not have a-ls command, usually starting with a command parameter. s command is the same as the dir command under DOS is used to list files under the directory, the-l parameter in Linux general role is to display the details, the-s parameter is used in Linux and the general purpose of using the-L is to list the size of each file in blocks.

The difference between the LS command and the Find command in 2.linux

The Find command is to find the meaning of the lookup; When you know which file it is, you can find the sub-file with LS, but you can use the Find command to find the folder when you don't know what the drive letter is.

Resources

1. In-depth understanding of computer systems

2.http://zhidao.baidu.com/question/588990569.html?fr=iks&word=linux++ls&ie=gbk

3. Wu Ziyi Students ' blogs

Information Security system Design Foundation Nineth Week study Summary