What Is Linux?
Like macOS, Windows & iOS. Linux is a operating System.
Now let's move to Commands used in Linux....
Commands
User information Commands
$ who
:- who command is used to display users who are logged on the system, including the terminals they are connecting from.$ id
:- used to print the genuine and effective user ID and group ID.whoami
:- Show your username
$ uname -a
:- Show system and kernel.$ date
:- Show system date$ uptime
:- Show uptime
Directory Operations
$ pwd
:- Show current directory$ mkdir dir
:- Make directory dir$ cd dir
:- Change directory to dir$ cd ..
:- Go up a directory
File Operations
$ rm filename
:- to remove file name$ ls
:- List files$ ls -l
:- detailed listing of the files and directories in the current directory.$touch filename
:- to create a new file.$cat filename
:- to display the contents of a file.$cp source/filename destination/
:- To create the copy of a file. It will create the new file in destination with the same name and content as that of the file ‘filename’.
$mv source/filename destination/
:- To move a file from source to destination. It will remove the file filename from the source folder and would be creating a file with the same name and content in the destination folder.
$mv filename new_filename
:- To rename a file. It will rename the filename to new_filename or in other words, it will remove the filename file and would be creating a new file with the new_filename with the same content and name as that of the filename file.
tail file1
:- Show last 10 lines of file1
head file1
:- Show first 10 lines of file1
File Permissions
First digit is owner permission, second is group and third is everyone.
Calculate permission digits by adding numbers below.
- 4 read (r)
- 2 write (w)
- 1 execute (x)
Commands for File Permissions
chmod 775 file
:- Change mode of file to 775