Linux Learning Note II: File processing commands for Linux

1. File processing command: LS

Role: Display directory files

Syntax: LS [options] [file or directory]

[option]:-a Show all files, including hidden files

-L Show more information

-D View Directory properties

[File or directory]: defaults to the current path as an argument when omitted

Instance:

· LS Displays information about all files (not including hidden files) under the current folder

· Ls-l Show details of all files (excluding hidden files) under the current folder

· Ls-ld Show details of the current folder

Tip: To view the information for a folder, you must add the-d parameter; To view detailed parameters, you must add the-l parameter.

2. Properties of the file

When you use the Ls-l hello.txt command, you will see details about the Hello.txt file in the current directory. As follows:

Drwxr-xr-x   2  root  root  4096 12-01 20:52 bin

This string of information from left to right means the following:

Type [Owner's permissions] [Permissions of the owning group] [Other people's rights] [Number of hard links] Owner [Owning group] [File Size] [Last modification time or creation time] Name

[Type]:d indicates that the bin is a directory.] D means directory-represents a binary file L represents a soft link file link

[Owner's permission]:rwx indicates that the owner has permission to read, write, and execute the directory.]

[The permission of the owning group is]:r-x, which indicates that the owning group has read and execute permissions on the directory.]

[Other people's permissions are]:r-x, indicating that the owner, someone outside the owning group, has permission to read and execute the directory.]

[Hard link number]:2. Indicates that there are two hard links

[Owner]: Owner is root. Note that the owner is not necessarily the creator, because ownership of the file or directory can be transferred.

[Owning group]: the directory belongs to the root user group

Note that for files and folders, the corresponding meanings of rwx are different. They have the following meanings:

R Read permission (file) to view the contents of a file (a folder) to list content in a directory

W Write permission (file) can modify the file contents (folder) can be created in the directory, delete files

X Execute permissions (files) can execute files (folders) can enter directory

3. Switch directory: CD

Syntax: CD [catalog]

Cd.. Switch to the previous level directory

CD/switch to the root directory (the left slash in Linux indicates the root directory)

Cd/home/chanshuyi/desktop switch to the Desktop directory

4. Display working directory: PWD

Syntax: pwd

Function: Displays the current path

5. Create a file Touch

Syntax: touch [filename]

Action: Create an empty file

Example: Creating a Hello.txt file $touch hello.txt (default current path)

6. Create Directory MkDir

Syntax: mkdir [directory name]

Role: Create a new directory

Example: Creating a Newdir folder $mkdir Newdir

7. copy files or directories CP

Syntax: CP [Options] [source file or directory] [destination directory]

[Option]:-r Assignment directory (need to be added when copying directories)

Function: Assign a file or directory

Example: CP hello.txt./hello.txt copy Hello.txt to the parent directory

Cp-r newdir./newdir Copy the Newdir folder to the parent directory

8. Moving files, renaming MV

Syntax: MV [source file or source directory] [destination directory]

Action: Move file, rename. In fact, the name of the change or file movement, when you move a file to the original folder is renamed.

Example: MV hello.txt~ hello.txt renaming hello.txt~ file to Hello.txt

9. Delete file rm

Syntax: RM [Options] [file or directory]

[option]-R Remove Directory-F Force Delete no reminder

Action: Delete a file or directory

Example: RM hello.txt Delete hello.txt file

rm-r Hello Delete Hello folder

10. display file Contents cat

Syntax: cat [filename]

Function: Display file contents

Example: $cat hello.txt Display the contents of a Hello.txt file

11, paging to view the contents of the file more

Syntax: more [filename]

Role: For paging through long-content files

Operation Key: (space) or F display next page

(Enter) to display the next line

Q or Q exit

12. View the first few lines of the file head

Syntax: head [options] [filename]

[option]-n indicates the first n rows are displayed

Example: $head -20/etc/services display the first 20 lines of a file

13. View the end of the file in a few lines tail

Syntax: tail [options] [file name]

[option]-n Specifies that the end n rows are displayed

-F Dynamic Display of file contents (i.e. Page view)

14. Generate Link File ln

Syntax: ln [options] [source file] [target file]

[option]-s to create a soft link (default is to create a hard link)

Note: A soft link is equivalent to a shortcut, whereas a hard link is equivalent to a copy + sync update.

Example: $LN-S/etc/issue/issue.soft create a soft link for the issue file

$LN/etc/issue/issue.hard Create a hard link for the issue file

Note: Hard links cannot be generated across file systems, and soft links can. (Cross-file systems refer to files that cross partitions, such as/test partitions, that cannot be created under a hard link to/(root directory).) Here the/test is a partition, not the test directory under the root directory Oh.

Next: Linux Learning Note II: Linux Permissions processing command

Linux Learning Note II: File processing commands for Linux