BASH/C2/Introduction-to-BASH-Shell-Scripting/Khasi

Time	Narration
00:01	Dear friends, welcome to the Spoken tutorial on Introduction to BASH shell scripting.
00:08	In this tutorial, we will learn:
00:10	About different types of Shells
00:13	To write a Bash Shell script and
00:16	To execute it.
00:18	To follow this tutorial, you should be familiar with Linux Operating System.
00:25	If not, then for relevant Linux tutorials, please visit our website which is as shown.
00:32	For this tutorial, I am using:
00:35	Ubuntu Linux 12.04 OS and
00:39	GNU Bash version 4.1.10.
00:43	Please note, GNU Bash version 4 or above is recommended for practice.
00:50	Let us start with an introduction.
00:53	We will see what a Bash Shell is.
00:56	Bash Shell is a command language interpreter that executes commands.
01:02	These commands are read from the standard input device.
01:07	The input device can be-
01:09	your keyboard
01:11	or a simple text file.
01:14	Let me show you what is a Bash Shell.
01:16	Open the terminal window by pressing Ctrl+Alt+T keys simultaneously on your keyboard .
01:24	This will open the Gnome terminal.
01:27	To check which type of shell we are using, type: echo space dollar sign SHELL (in capital).
01:38	Press Enter.
01:40	You will see the output printed on the next line as: slash bin slash bash.
01:47	This indicates that we are using the Bash Shell.
01:51	Now, let us know different types of Shells available.
01:56	Let us switch back to our slides. Bourne Shell-
02:00	This was original UNIX shell written by Stephen Bourne.
02:06	It lacked interactivity provided by most modern shells today.
02:11	C Shell-It provides features lacking in Bourne Shell .
02:16	K Shell- It was created by David Korn.
02:20	It has features of both, B Shell and C Shell along with some additional features.
02:27	Bash Shell-
02:30	The Bash Shell was developed by GNU Project.
02:32	It is based on B Shell language.
02:35	It has features of C and K Shells.
02:40	TC Shell-It is the default Shell of FreeBSD and its descendants.
02:46	Z shell-
02:49	It is a Shell designed for interactive use.
02:52	It has many useful features of ksh, bash and tcsh.
02:58	Now let us see what a Bash Shell script is.
03:02	The Bash Shell script contains a series of Bash commands in plain text file.
03:08	It tells the Shell to execute this text file instead of typing the commands.
03:15	Let us see how to write a simple Bash script.
03:20	We will test the echo command which will print Hello World on the terminal.
03:25	Go back to the terminal.
03:29	Now, type: echo space within double quotes Hello world
03:35	and press Enter.
03:37	This prints Hello World on the terminal.
03:40	The command worked as expected.
03:43	Now, what if we want to use this command in a file?
03:47	Just put this command in a file and execute that file.
03:52	I will use gedit text-editor for this purpose.
03:57	You are free to use your favorite text-editor.
04:00	I want to create my file on the Desktop.
04:03	So, type: cd space Desktop
04:07	Press Enter.
04:09	Now, type: gedit space hello underscore world dot sh space &(ampersand sign).
04:20	gedit is the text editor. 'Hello underscore world dot sh' is the file name and
04:27	we use the & (ampersand) to free up the prompt.
04:32	Now press Enter.We have opened a new file named hello_world.sh using gedit.
04:40	Now, type: hash exclamation mark front slash bin front slash bash
04:47	This is the first line of every bash script.
04:51	It is called as shebang or bang line.
04:55	Press Enter.
04:57	Now, let's add a comment to the file by typing:
05:00	hash space My first Bash script
05:06	Remember that any line after hash is treated as a comment.
05:11	And comments are ignored by the Bash interpreter.
05:15	Now we can add the command which we used earlier.
05:19	Press Enter and type: echo space within double quotes Hello world.
05:27	Press Enter.Type: echo space dollar-sign SHELL (in Capital)
05:34	press Enter.Type: echo space backtick date backtick
05:41	backtick symbol is present on the key which has tilde character.
05:47	Now, click on Save to save the file.
05:50	Let us execute. Come back to our terminal.
05:55	First, we have to make the file executable.
05:58	For this, type: chmod space plus x space hello underscore world dot sh
06:09	and press Enter.
06:12	Now, type:
06:14	dot slash hello underscore world dot sh
06:19	Press Enter.
06:22	You can see Hello World is displayed on the terminal.
06:27	The shell type is displayed on the next line. i.e slash bin slash bash
06:32	and day, month, time, time zone and year are displayed.
06:38	The output may vary depending on the system.
06:43	Let us go back to our slides and summarize.
06:46	In this tutorial, we have learnt about:
06:48	Different types of Shells
06:50	Bash Shell .Bash Shell script.
06:52	To write a simple Shell script and to execute the script.
06:57	As an assignment- write a simple script to display the message -“Welcome to Bash learning”
07:03	and “***************” (asterisks) on separate line.
07:06	Watch the video available at the link shown below.
07:10	It summarizes the Spoken-Tutorial project.
07:13	If you do not have good bandwidth, you can download and watch it.
07:17	The Spoken-Tutorial Project team:
07:20	Conducts workshops using spoken tutorials.
07:22	Gives certificates to those who pass an online test.
07:26	For more details, please write to contact@spoken-tutorial.org
07:34	Spoken Tutorial Project is a part of the "Talk to a Teacher" project.
07:39	It is supported by the National Mission on Education through ICT, MHRD, Government of India.
07:45	More information on this mission is available at the link shown below. http://spoken-tutorial.org/NMEICT-Intro
07:51	The script has been contributed by FOSSEE and Spoken-Tutorial teams.
07:56	This is Ashwini Patil from IIT Bombay, signing off. Thank you for joining.

Contributors and Content Editors

Meboreen Mary