General Linux Information

General Linux Information

1. Everything in Linux is a file including the hardware and even the directories.

2. # : Denotes the super(root) user

3. $ : Denotes the normal user

4. /root: Denotes the super user’s directory

/home: Denotes the normal user’s directory.

5. Switching between Terminals

§ Ctrl + Alt + F1-F6: Console login

§ Ctrl + Alt + F7: GUI login

6. The Magic Tab: Instead of typing the whole filename if the unique pattern for a particular file is given then the remaining characters need not be typed and can be obtained automatically using the Tab button.

7. ~(Tilde): Denotes the current user’s home directory

8. Ctrl + Z: To stop a command that is working interactively without terminating it.

9. Ctrl + C: To stop a command that is not responding. (Cancellation).

10. Ctrl + D: To send the EOF( End of File) signal to a command normally when you see ‘>’.

11. Ctrl + W: To erase the text you have entered a word at a time.

12. Up arrow key: To redisplay the last executed command. The Down arrow key can be used to print the next command used after using the Up arrow key previously.

13. The history command can be cleared using a simple option –c (clear).

14. cd : The cd command can be used trickily in the following ways:

cd : To switch to the home user

cd * : To change directory to the first file in the directory (only if the first file is a directory)

cd .. : To move back a folder

cd - : To return to the last directory you were in

15. Files starting with a dot (.) are a hidden file.

16. To view hidden files: ls -a

17. ls: The ls command can be use trickily in the following ways:

ls -lR : To view a long list of all the files (which includes directories) and their subdirectories recursively .

ls *.* : To view a list of all the files with extensions only.

18. ls -ll: Gives a long list in the following format

drwxr-xr-x 2 root root 4096 2010-04-29 05:17 bin where

drwxr-xr-x : permission where d stands for directory, rwx stands for owner privilege, r-x stands for the group privilege and r-x stands for others permission respectively.

Here r stands for read, w for write and x for executable.

2=> link count



4096=> directory size

2010-04-29=>date of creation

05:17=> time of creation

bin=>directory file(in blue)