C-and-C++/C4/Understanding-Pointers/English-timed

Time	Narration
00.01	Welcome to the spoken tutorial on Pointers in C and C++
00.06	In this tutorial we will learn,
00.08	Pointers.
00.10	To create Pointers.
00.12	And operations on Pointers.
00.14	We will do this with the help of an example
00.18	To record this tutorial I am using Ubuntu operating system version 11.10
00.25	gcc and g++ compiler version 4.6.1 on Ubuntu
00.31	Let us start with an introduction to pointers
00.34	Pointers point to the locations in memory.
00.38	Pointers store the memory address.
00.41	It also gives value stored at that address.
00.45	Now, let us see an example on pointers
00.48	Note that our file name is pointers_demo.c
00.54	Let us go through the code now
00.56	This is our header file as stdio.h
01.00	This is our main function
01.03	Here we have long integer num assigned value 10.
01.09	Then we have declared a pointer ptr.
01.12	Asterisk sign is used to declare a pointer.
01.16	This pointer can point to type long int.
01.20	In the printf statement ampersand is used for retrieving memory address of the variable.
01.28	So ampersand num will give the memory address of num.
01.33	This statement will print the address of the variable num.
01.37	Over here ptr stores the address of num.
01.41	This statement will print the address of ptr.
01.45	Sizeof function will give the size of ptr.
01.49	This is will give the value of ptr.
01.51	That is the memory address of num.
01.54	And here asterisk ptr will give the value at the address.
01.59	So using asterisk will not give the memory address.
02.03	Instead it will give the value.
02.06	%ld is a format specifier for the long int
02.10	Now, let us execute the program
02.13	Open the terminal window by pressing Ctrl, Alt and T keys simultaneously on your keyboard
02.21	To compile type gcc space pointers underscore demo dot c space hyphen o space point
02.32	Press Enter
02.34	Type dot slash point. Press Enter
02.39	The output is displayed
02.42	We see that the num address and ptr value is same.
02.48	Where as memory address of num and ptr are different.
02.53	Then the size of pointer is 8 bytes.
02.57	Also the value pointed by ptr is 10 which was assigned to num.
03.03	Now let us see the same program in C++.
03.07	Note that our file name is pointer underscore demo.cpp
03.13	Here we have few changes like the header file as iostream
03.19	Then we are using the std namespace
03.23	And we have the cout function in place of printf function
03.28	Rest all the things are similar
03.30	Let us execute the program. Come back to our terminal.
03.34	To compile type g++ space pointers_demo.cpp space hyphen o space point1, press Enter
03.50	Type dot slash point1, press Enter
03.55	We can see that the output is similar to our C program
04.00	This brings us to the end of this tutorial.
04.03	Come back to our slide
04.05	Let us summarize
04.06	In this tutorial, we learnt
04.08	About the pointer.
04.10	To create a pointer.
04.12	And operation on pointer.
04.14	As an assignment, write a C and C++ program,
04.18	To declare a variable and pointer.
04.21	Store the address of variable in the pointer.
04.24	And print the value of the pointer.
04.27	Watch the video available at the link shown below
04.30	It summarizes the Spoken Tutorial project
04.33	If you do not have good bandwidth, you can download and watch it
04.37	The Spoken Tutorial Project Team
04.39	Conducts workshops using spoken tutorials
04.43	Gives certificates to those who pass an online test
04.47	For more details, please write to, contact@spoken-tutorial.org
04.53	Spoken Tutorial Project is a part of the Talk to a Teacher project
04.58	It is supported by the National Mission on Education through ICT, MHRD, Government of India
05.06	More information on this Mission is available at the link shown below
05.10	This is Ashwini Patil from IIT Bombay signing off
05.14	Thank You for joining.

Contributors and Content Editors

Kavita salve, Krupali, PoojaMoolya, Pratik kamble, Sandhya.np14, Sneha