Common basic commands for "Linux" Linux

Ext.: http://blog.csdn.net/xiaoguaihai/article/details/8705992

There are many common commands in Linux that must be mastered, and here I will learn some common basic commands that I learned from Linux to share with you and hope to help you.

This is the bird in the book I have done a bit, I hope not to deal with copyright issues.

1. Instructions for displaying dates: date

2. Instructions for displaying the calendar: Cal

3. Simple and easy to use calculator: BC

Why would 10/100 become 0? This is because BC presets only output integers, and if you want to output a decimal point, you have to execute Scale=number, which is the number of decimal places, for example:

4. Important several hotkeys [Tab],[ctrl]-c, [ctrl]-d

[Tab] Key---with "command completion" not "file full" function

[Ctrl]-c button---Let the current program "Stop"

[ctrl]-d Key---usually means: "Keyboard input ends (end of File, EOF end ofinput)" meaning; In addition, he can be used to replace exit

5, man

Exit with Q,

Man-f Mans

6. Data synchronously written to disk: Sync

Enter sync, and the data that has not been updated in memory will be written to the hard drive, so this led makes it important before the system shuts down and restarts cookbook. It's best to do it several times!

7, the customary shutdown command: Shutdown

In addition, it should be noted that the time parameter must be added to the directive, otherwise shutdown will automatically jump to Run-level 1 (that is, the single-person maintenance of the login), so it is a headache! Here are a few examples of time parameters:

Restart, shutdown: reboot, Halt,poweroff

8. Switch execution level: init

There are seven levels of execution in Linux:

--run Level 0: Shutdown

--run Level 3: Plain text mode

--run Level 5: Graphics interface mode included

--run Level 6: Restart

Use the init command to switch between the modes:

If you want to shut down, you can also use the following instructions to shut down your computer, in addition to the shutdown-h now and Poweroff above:

9. Change the file's owning group: CHGRP

10. Change the file owner: Chown

He can also change the name of the group directly dwellings

11, change the permissions of the file: chmod

There are two ways to set permissions, and you can use numbers or symbols to change permissions.

--Digital Type change file permissions:

--Symbol Type change file permissions:

12. View version information, etc.

13. Change Directory: CD

14. Show current directory: PWD

15. Create a new directory: mkdir

It is not recommended to use the-P option, because you are worried that if you typo, the directory name will become messy.

16. Delete "Empty" directory: RmDir

17. Display of files and directories: LS

18. Copying Files or directories: CP

19. Removal of files or directories: RM

20. Moving files and directories, or renaming: MV

21, get the path of the file name and directory name: Basename,dirname

22, starting from the first line to display the contents of the archive: Cat

23. Starting from the last line: TAC (can see that the TAC is backwards written by cat)

24, display the time, by the output line number: NL

25, one page of the contents of the file: more

26, similar to more, but better than more, he can page forward: less

27, only a few lines: Head

28, only look at the end of a few lines: tail

29. Read the contents of the file in binary position: OD

30. Modify the file time or create a new profile: Touch

31. File Preset Permission: Umask

32. Profile File Hidden properties: Chattr

33. Show file Hidden properties: Lsattr

34. Observation file type: Files

35, look for "execution gear": which

36. Find specific files: Whereis

37. Find specific files: Locate

38. Find a specific file: Find

39. Compress files and read compressed files: Gzip,zcat

40. Compress files and read compressed files: Bzip2,bzcat

41. Compressing files and reading compressed files: Tar

PS:IP. Gzip. What's the difference between tar? How big is that compression?

Tar is packaging, not compression, just putting a bunch of files into a file. Gzip is a technique used to improve the performance of Web applications by compressing the content of Web pages and then transmitting them over the HTTP protocol.
Zip is needless to say, the mainstream compression format.
Zip The latest compression algorithm is still very good, it is recommended to use the ZIP format, full platform universal.

Tar is not how to compress, compression rate of 100%, mainly always packaged, zip compression rate look at the file type, JPG is not how compression rate, but BMP very high gzip generally higher than zip

Well, exhausted, finally finished, hope to be able to help everyone.

Common basic commands for "Linux" Linux