BASH/C3/More-on-functions/Gujarati
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Time | Narration |
00:01 | More on functions પરનાં સ્પોકન ટ્યુટોરીયલમાં સ્વાગત છે. |
00:06 | આ ટ્યુટોરીયલમાં, આપણે શીખીશું |
00:09 | ફંક્શનમાં આર્ગ્યુંમેંટ પસ કરતા. |
00:11 | ફંક્શનમાં local variable વ્યાખ્યિત કરતા. |
00:16 | ફંક્શનમાં global variable વ્યાખ્યિત કરતા. |
00:19 | ઉદાહરણ સાથે સમજીએ. |
00:23 | આ ટ્યુટોરીયલનાં અનુસરણ માટે તમને બેશમાંનાં Shell Scripting નું જ્ઞાન હોવું અનિવાર્ય છે. |
00:28 | જો નથી, તો સંદર્ભિત ટ્યુટોરીયલો માટે કૃપા કરી દર્શાવેલ અમારી વેબસાઈટનો સંદર્ભ લો, (http://www.spoken-tutorial.org) |
00:35 | આ ટ્યુટોરીયલ માટે હું વાપરી રહી છું. |
00:37 | ઉબુન્ટુ લીનક્સ 12.04 ઓપરેટીંગ સીસ્ટમ |
00:42 | GNU BASH આવૃત્તિ 4.2 |
00:45 | પા કરી નોંધ લો, આ ટ્યુટોરીયલનાં અભ્યાસ માટે GNU Bash આવૃત્તિ 4 કે તેથી વધુ આગ્રહ કરીએ છીએ. |
00:52 | ચાલો ફંક્શન માં આર્ગ્યુંમેંટ કેવી રીતે પાસ કરવું અને કેવી રીતે વાપરવું તે શીખીએ. |
00:59 | ચાલો હું 'function_(underscore) parameters.sh' ફાઈલ ખોલું. |
01:05 | આ shebang line. છે. |
01:08 | say_(underscore)welcome આ આપણા ફંક્શન નું નામ છે. |
01:13 | Open curly bracket opens the function definition. |
01:18 | $(Dollar)1 is the first positional parameter |
01:22 | $(Dollar)2 is the second postional parameter |
01:26 | Close curly bracket closes the function definition. |
01:30 | Here, the function 'say_welcome' is called with arguments. |
01:35 | The syntax is, function name i.e. say welcome ...followed by the arguments within double quotes, i.e. Bash and learning. |
01:49 | In a similar manner, I will call the same function with a different set of arguments. So, I havesay_welcome space within double quote functions in space and within double quote Bash. |
02:05 | Save the file and go to the terminal. |
02:08 | Type chmod space plus x space function underscore parameters dot sh |
02:17 | Press Enter. |
02:19 | Type dot slash function underscore parameters dot sh |
02:26 | Press Enter. |
02:28 | We see that the positional parameters were substituted by the arguments passed to a function. |
02:36 | Dollar 1($1) was substituted by the string Bash and Dollar 2($2) with learning. |
02:45 | Then again, Dollar 1($1) was substituted by functions in and Dollar 2($2) with Bash. |
02:55 | In Bash, variables can be declared as local variables and global variables. |
03:01 | Local variable: |
03:03 | It's value will be valid within the function in which it is defined. |
03:10 | Local variables are declared using keyword local |
03:15 | Global variable |
03:17 | The value of a global variable can be accessed throughout a Bash script. |
03:24 | Let us learn these 2 ways to declare a variable within a function. |
03:29 | Let me open a file named function_(undescore)local.sh' |
03:35 | This is the shebang line. |
03:39 | Function name is say_(underscore) hello |
03:43 | Here, variable first_name is declared with keyword local. |
03:49 | Which means, its value will be valid within the function say_hello only. |
03:55 | A variable declared without any keyword,is treated as a global variable. |
04:01 | So, the variable last_name can be accessed throughout the script. |
04:08 | In this echo line, we will display the value of variables |
04:12 | first_name, |
04:14 | middle_name |
04:15 | And last_name |
04:17 | After this, we close the function. |
04:21 | Now, here the variable middle_name is declared without keyword. So, its value will be global throughout the script. |
04:30 | Once again, we will call the function here. |
04:34 | We pass two arguments to this function call, namely, “Pratik” and “Patil”. |
04:41 | These echo statements will display the value of variables |
04:45 | $first_name, |
04:46 | $middle_name and $last_name |
04:51 | Please keep in mind that variable first_name is a local variable. |
04:57 | Save the file and go to the terminal. |
05:00 | Type chmod space plus x space function underscore local dot sh |
05:09 | Press Enter. |
05:11 | Type dot slash function underscore local dot sh |
05:16 | Press Enter. |
05:18 | The first line of output displays the message Hello Pratik K Patil. |
05:25 | Here, the variable first_name that contains value Pratik is local. |
05:31 | Which means the value is limited to the function. |
05:35 | Now, let us see how the local variable behaves outside the function. |
05:41 | Here, nothing is displayed in first_name. |
05:44 | This is because the value of first_name is local to the function. And it is not available outside the function. |
05:53 | middle_name and last_name are printed as they are global variables. |
05:59 | Hope the difference is clear to you. |
06:02 | Let us now summarise. |
06:04 | In this tutorial, we learnt |
06:07 | To pass arguments to a function .To declare Local variable in a function |
06:14 | To declare Global variable in a function. with the help of a few examples |
06:20 | As an assignment. |
06:22 | Write a program, |
06:23 | Where the function accepts two arguments. The function should multiply the two arguments. |
06:31 | Make 3 function calls with arguments (1, 2), (2, 3) and (3, 4) |
06:39 | Watch the video available at the link shown below. |
06:43 | It summarises the Spoken Tutorial project.If you do not have good bandwidth, you can download and watch it. |
06:51 | The Spoken Tutorial Project Team.Conducts workshops using spoken tutorials. Gives certificates to those who pass an online test |
07:00 | For more details, please write to contact@spoken-tutorial.org |
07:07 | Spoken Tutorial Project is a part of the Talk to a Teacher project. |
07:11 | It is supported by the National Mission on Education through ICT, MHRD, Government of India.More information on this Mission is available at http://spoken-tutorial.org\NMEICT-Intro |
07:26 | The script has been contributed by FOSSEE and Spoken-Tutorial teams. |
07:31 | This is Ashwini Patil from IIT Bombay signing off.Thank you for joining. |