C-and-C++/C3/String-Library-Functions/English-timed
From Script | Spoken-Tutorial
Revision as of 12:57, 7 February 2014 by PoojaMoolya (Talk | contribs)
| Time | Narration
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| 00.01 | Welcome to the spoken-tutorial on String Library Functions in C
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| 00.07 | In this tutorial we will learn, |
| 00.09 | String Library Functions |
| 00.11 | We will do this with the help of some examples |
| 00.15 | To record this tutorial, I am using |
| 00.18 | Ubuntu Operating System version 11.10, |
| 00.22 | gcc Compiler Version 4.6.1 |
| 00.27 | Let us start with an introduction to string library functions. |
| 00.31 | These are the group of functions implementing operations on strings. |
| 00.36 | Various operations such as copying, concatenation, searching etc are supported. |
| 00.44 | Let us see some of the string library functions |
| 00.48 | Here we have the strncpy function |
| 00.52 | The syntax for this is strncpy(char str1, char str2, and int n ) |
| 01.02 | It copies first n characters of string str2 into string str1 |
| 01.09 | example, char strncpy( char hello, char world, 2) |
| 01.16 | The output will be Wollo |
| 01.21 | Here we have Wo from the string 2 and rest of the characters from string 1 |
| 01.29 | Now we will see strncmp function, the syntax for this is strncmp(char str1, char str2, and int n) |
| 01.42 | It will compare first n characters of string 2 with string 1 |
| 01.48 | example int strncmp(char ice, char icecream, and 2); |
| 01.55 | The output will be 0 |
| 01.58 | Now we will see how to use the string library functions. |
| 02.02 | I am going to show you some of the commonly used string functions. |
| 02.07 | I have already typed the program on the editor, |
| 02.10 | I will open it |
| 02.12 | Here we have the string length function |
| 02.15 | Note that our filename is strlen.c. |
| 02.20 | In this we will find the length of the string |
| 02.23 | These are the header files as stdio.h and string.h. |
| 02.29 | This is our main function |
| 02.31 | Here we have a character variable 'arr', |
| 02.35 | It stores a value 'Ashwini' |
| 02.38 | Then we have an integer variable len1 |
| 02.42 | Here we will find the lenght of the string using strlen function |
| 02.48 | The result will be stored in len1 |
| 02.52 | Then we print the string and the length of the string. |
| 02.56 | And this is our return statement |
| 02.59 | Now let us execute the program |
| 03.01 | Open the terminal window by pressing
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| 03.04 | Ctrl, Alt and T keys simultaneously on your keyboard |
| 03.09 | To compile Type: "gcc" space "strlen.c" space “-o” space “str1”. Press Enter |
| 03.19 | Type (dot slash) ./str1. Press Enter |
| 03.24 | The output is displayed as |
| 03.26 | string = Ashwini, Length = 7 |
| 03.30 | You can count here. 1,2,3,4,5,6, and 7 |
| 03.37 | Let us see another string function |
| 03.40 | Here we have the string copy fuction |
| 03.43 | Note that our filename is strcpy.c |
| 03.48 | In this we will copy the source string into the target string |
| 03.53 | Here we have Ice in the source string, it will be copied to the target string |
| 03.59 | This is our strcpy function |
| 04.02 | Here we will print the source string and the target string |
| 04.07 | Let us execute and see |
| 04.09 | Come back to our terminal |
| 04.11 | To compile type gcc space strcpy.c space hyphen o space str2. Press Enter
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| 04.20 | Type (dot slash)./str2 Press Enter |
| 04.24 | The output is displayed as |
| 04.26 | source string = Ice |
| 04.29 | target string = Ice |
| 04.32 | Now let us see another string function |
| 04.34 | Now we will see the string compare function |
| 04.37 | Note that our filename is strcmp.c |
| 04.42 | In this we will comapre two strings |
| 04.46 | Here we have character variables as str1 and str2 |
| 04.52 | str1 stores the value as 'Ice' and str2 stores the value as 'Cream'. |
| 04.58 | Here we have interger variables as i and j |
| 05.03 | In this we will compare the string using the strcmp function |
| 05.08 | Here we compare str1 ie: 'Ice' with 'Hello' |
| 05.14 | The result is stored in i |
| 05.16 | In this we will compare string2 ie: 'Cream' with 'Cream' |
| 05.23 | The result is stored in j |
| 05.25 | Then we print both the results |
| 05.28 | And this is our return statement |
| 05.31 | Let us execute the program. |
| 05.33 | Come back to our terminal. |
| 05.35 | To compile type gcc space strcmp.c space hyphen o space str3 |
| 05.46 | Press Enter |
| 05.47 | Type (dot slash)./str3 |
| 05.50 | The outpur is displayed as 1,0 |
| 05.54 | Come back to our program |
| 05.56 | Here we get 1 and here we get as 0 |
| 06.01 | Let us come back to our slides |
| 06.04 | Let us summarize, |
| 06.06 | In this tutorial we learned,
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| 06.07 | String library functions |
| 06.09 | strlen() |
| 06.11 | strcpy() |
| 06.13 | strcmp()
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| 06.14 | strncpy() |
| 06.16 | and strncmp() |
| 06.19 | As an assignemnt, |
| 06.21 | Write a C Program to concatenate String best and String bus. |
| 06.25 | Hint: strcat(char str1, char str2); |
| 06.32 | Also explore the other functions in string library. |
| 06.36 | Watch the video available at the link shown below |
| 06.39 | It summarizes the Spoken Tutorial project |
| 06.42 | If you do not have good bandwidth, you can download and watch it |
| 06.46 | The Spoken Tutorial Project Team |
| 06.49 | Conducts workshops using spoken tutorials |
| 06.52 | Gives certificates to those who pass an online test |
| 06.56 | For more details, please write to, contact@spoken-tutorial.org
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| 07.03 | Spoken Tutorial Project is a part of the Talk to a Teacher project |
| 07.08 | It is supported by the National Mission on Education through ICT, MHRD, Government of India |
| 07.15 | More information on this Mission is available at the link shown below |
| 07.20 | This is Ashwini Patil from IIT Bombay signing of. |
| 07.24 | Thank you for joining. |