Linux Shell Basics Part1

This tutorial is a brief introduction to the LINUX SHELL programming

First of all What is a Terminal in Linux?

Terminal is an Interface for Linux where you can Enter your commands and execute them. This is similar to the Command Prompt Application in Windows Operating Systems.

This Helps you to perform various operations like File Manipulation,Process management, Memory Management ,etc.

Now Lets get started to see How to Work with Terminal. The Terminal Window Shown Below is the Terminal Window of Ubuntu.

To View the Terminal in Ubuntu Press CTRL + ALT + T.

As You can See in the Above Image.

You Have something like “kamar@kamar-Aspire-E1-531”

here “kamar” is the username of my Ubuntu OS and “kamar-Aspire-E1-531” is my Laptop Name.

Now You Will Study the First Command “ls”

The Command “ls” is used to display all the Files and Directories in your Current Folder that is “home/kamar” as my username is “kamar”

Just type “ls” and Press Enter

As You can see in the above image it Displays the name of the Directories like Templates,Videos,Ubuntu One,etc and Also it Displays Files like kamar.kmy, and .mp3 file etc

There are various Options for the ls command like

ls [-a] [-A] [-b] [-c] [-C] [-d] [-f] [-F] [-g] [-i] [-l] [-L] [-m] [-o] [-p] [-q] [-r] [-R] [-s] [-t] [-u] [-x] [pathnames]

-a	Shows you all files, even files that are hidden (these files begin with a dot.)
-A	List all files including the hidden files. However, does not display the working directory (.) or the parent directory (..).
-b	Force printing of non-printable characters to be in octal \ddd notation.
-c	Use time of last modification of the i-node (file created, mode changed, and so forth) for sorting (-t) or printing (-l or -n).
-C	Multi-column output with entries sorted down the columns. Generally this is the default option.
-d	If an argument is a directory it only lists its name not its contents.
-f	Force each argument to be interpreted as a directory and list the name found in each slot. This option turns off -l, -t, -s, and -r, and turns on -a; the order is the order in which entries appear in the directory.
-F	Mark directories with a trailing slash (/), doors with a trailing greater-than sign (>), executable files with a trailing asterisk (*), FIFOs with a trailing vertical bar (|), symbolic links with a trailing at-sign (@), and AF_Unix address family sockets with a trailing equals sign (=).
-g	Same as -l except the owner is not printed.
-i	For each file, print the i-node number in the first column of the report.
-l	Shows you huge amounts of information (permissions, owners, size, and when last modified.)
-L	If an argument is a symbolic link, list the file or directory the link references rather than the link itself.
-m	Stream output format; files are listed across the page, separated by commas.
-n	The same as -l, except that the owner's UID and group's GID numbers are printed, rather than the associated character strings.
-o	The same as -l, except that the group is not printed.
-p	Displays a slash ( / ) in front of all directories.
-q	Force printing of non-printable characters in file names as the character question mark (?).
-r	Reverses the order of how the files are displayed.
-R	Includes the contents of subdirectories.
-s	Give size in blocks, including indirect blocks, for each entry.
-t	Shows you the files in modification time.
-u	Use time of last access instead of last modification for sorting (with the -t option) or printing (with the -l option).
-x	Displays files in columns.
-1	Print one entry per line of output.
pathnames	File or directory to list.

Now Lets Learn Another Command “pwd”
“pwd” stands for Present Working Directory



This Command Will Display the Complete path of the Present Working Directory

In Above Image you can see that the terminal displays “/home/kamar” as it is my current working Directory.
Now If your Username is Something Like “xyz” it would display “home/xyz”



To Be Continued.....