 Hello friends, I am Sanjay Gupta. In this video, I am going to demonstrate you the use of str-alien predefined function with the help of c-programming. Before starting, you can note my information, you can follow or subscribe my YouTube channel through the URL youtube.com slash sanjaygupta underscore tech school. You can download my programming app Techimus which is available on Google Play. Now I am going to implement how you can use str-alien function which is predefined in string.h header file. So I am including two header files that is str-dio.h and string.h. So this str-alien is a predefined function and its header file is string.h. So str-alien function counts how many characters are available in a string. So now I am going to demonstrate you how it works. So suppose there is a string and I have an integer variable c. Now I am using printf which will display the message enter string on console to receive that string I am using datas. Now I want to count how many characters user entered inside str character array. So for that purpose I am using predefined function str-alien. So I have just passed str string into str-alien function. So str-alien is predefined function. So it will count number of characters which are available inside str and the result will be returned into c variable. Now I can print the value of c on console. So length equals to percent d and then c. So c will be printing the number of characters which are available inside str string and then return zero. So this way I have implemented this str-alien function which is predefined in string.h header file. Now I am going to execute this code. So I am entering the string sanjay. You can see the output it is showing six. So sanjay contains total six characters. That's why it is printing length as six. Notice that it is not counting null character which is available at the end of string. So before null character whatever is available in the str string str-alien function will count all those characters and the result will be assigned into the variable which is available in this str-alien function column. So here I have used c variable. So that's why c is printing the output on console. So this is the use of str-alien function which is predefined in string.h header file. So str-alien is the function which is counting total number of characters available in the string. So it's full form is string length. I hope you have understood whatever I have demonstrated to you in this video. If you want to watch more programming related videos you can follow or subscribe my youtube channel through the url youtube.com slash sanjay gupta underscore tech school. You can download my programming app tech image which is available on google play. Thank you for watching this video.