Linux Learning Notes (ii) Linux commands

First, command-line syntax:

　　command word [options] [parameters]

Note: Thecommands in Linux are case-sensitive.

Second, get command help:

1, help command: Help Xxx,shell internal instructions, used to obtain Linux internal commands. For example: Help and Help.

2, '--help ' option: XXX--help Gets the help information for the command. LS--help.

3, man command: Man xxx to display the Help manual in full-screen mode, press Q to exit. Man ls.

4. Info command: info xxx get help manual by Q exit in more detailed way. Info ls.

Third, file directory operation command:

　　1, ls: Display the contents of the directory

Common options:

-L: Displaying files and directories in long format

-A: Displays information for all subdirectories and files

-D: Displays the properties of the directory itself

-r: Displays the specified directory and all subdirectories

Wildcard characters:

?: matches one of the characters in the file.

*: matches any number of characters in the file.

　　2. CD: Change working directory

　　　　relative path: The path relative to the current working directory.

A, A. Start: Current path

B, two: Start: Top level Directory

C, one ~ start: Host Directory

D, one/old naughty: root directory

　　　　Absolute Path: The path that starts at the root of the system/home/xxx.

　　3. PWD: Show current directory

　　4. Du: Statistics Catalogue

-A: Statistics all files that are occupied by disk space.

-H: Statistical results are displayed in a personalized way, showing the file units

-S: Counts the total size of the controls that each parameter occupies.

　　5. mkdir: Create a new directory

-P: Creating nested Multi-level catalogs

Mkdir-p AAA/BBB/CCC Create a 3-level directory at a time without the-p error.

　　

Iv. File Operation commands

　　1. Touch: Create a new file. If the file does not exist, create an empty file and, if the file exists, update the file creation time, you can create multiple files at once.

Example: Touch file1.txt file2.txt//Simultaneous creation of 2 files

　　2. CP: Copy files or directories.

Options:

-F: Force replication.

-I: Alert the user to confirm.

-P: Keeps the property intact.

-r: Assigns all files and subdirectories.

Example: Cp-r mydir mydir_back

　　3. RM: Delete files or directories.

Options:

-F: Force delete directly.

-I: Alert the user to confirm.

-r: Deletes all files in the entire directory and directory.

By default, RM does not delete the directory. Use the--recursive (-R or-r) option to delete each given directory, along with all of its contents.

　　4, MV: Renaming or moving files or directories.

MV file1.txt file_first.txt: rename file1.txt to File_first.txt

MV File1.txt/home/file2.txt: Move file1.txt to/home/file2.txt

　　5. Find: Locate the file or directory.

Syntax: Find [Find scope] [find conditional expression]

Search criteria:

-name: Find by name

-size: Find by size

-user: Search by file Owner

-type: Find by File type

　　6. Which: Find the location of the command file.

Syntax: which command

Example: Which LS

　　7. File: View the type of files.

Syntax: File path

Example: File/usr/bin/ls

　　8. LN: Create a shortcut.

Syntax: LN [-S] source file or directory link file or destination directory

Shortcuts are mainly broken down into symbolic links and hard links.

Hard Links: You cannot create hard links to directories or create hard-linked files across partitions.

Symbolic link (soft link): You need ln to add the-s option.

For example: ln-s/home/zhengcheng/mydir/file1.txt/home/zhengcheng/Desktop//For file1.txt create soft links on desktop

　　

　　

Linux Common Command query:

20 commands for common Linux: http://www.oschina.net/translate/useful-linux-commands-for-newbies

Command query: http://www.jb51.net/linux/

Linux Learning Notes (ii) Linux commands