BASH/C2/More-on-Loops/English-timed
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| Time | Narration |
| 00:01 | Welcome to the spoken tutorial on Nested for loop in BASH |
| 00:07 | In this tutorial, we will learn Nested for loop With the help of an example. |
| 00:13 | To record this tutorial I am using Ubuntu Linux 12.04 Operating System and GNU BASH version 4.1.10 |
| 00:24 | Please note, GNU Bash version 4 or above is recommended for practice. |
| 00:31 | To learn this tutorial, you should be familiar with loops in Bash. |
| 00:37 | For relevant tutorials, please visit our website which as shown http://spoken-tutorial.org |
| 00:43 | Let us start with an introduction to nested loop. |
| 00:46 | A loop within a loop is known as nested loop. |
| 00:51 | Let us see the syntax Outer for loop expression 1, 2, 3 |
| 00:57 | Inner for loop expression 1, 2, 3 |
| 01:01 | statement 1 statement 2 |
| 01:04 | Closing Inner for loop Closing Outer for loop |
| 01:09 | Let us see an example on nested for loop. |
| 01:12 | First let us go through the directory structure. |
| 01:17 | Here is a directory on the Desktop named simple-nested-for. Let's open it. |
| 01:24 | We have subdirectories test, test2 and test3 and a Bash script. |
| 01:31 | In each sub-directory, there are multiple text files. |
| 01:36 | Now we will move on to our code. |
| 01:39 | This program displays all the files within each subdirectory. |
| 01:45 | Please note that the same can be acheived with a single line command ls -1 (hyphen one) -R(hyphen R) test*(test asterix) |
| 01:53 | But we will do it using a for loop. |
| 01:58 | Note that the name of our Bash script is nested-(Hyphen)for dot sh |
| 02:05 | This is our shebang line. |
| 02:08 | This is the outer for loop. |
| 02:10 | This for loop will check for directories starting with the name test. |
| 02:15 | First echo line will display the sub-directories name |
| 02:21 | The second echo line will create a blank line. |
| 02:25 | This is the inner for loop.It will check for files present within the directories. |
| 02:32 | ls displays the directory content. |
| 02:36 | -1 (hyphen one) is used to list one file per line. |
| 02:41 | Here we list the files.done ends the inner for loop. |
| 02:45 | This command prints a vertical line after completion of every cycle of outer for-loop. |
| 02:53 | done ends the outer for loop. |
| 02:57 | Let us execute the program. |
| 02:58 | Open the terminal by pressing ctrl+alt+t keys simultaneously on your keyboard. |
| 03:08 | Now, let us go to the directory where our Bash script is. |
| 03:13 | It is on the Desktop. |
| 03:15 | Type cd Desktop. Let us go in the folder simple-(Hyphen)nested-(Hyphen)for |
| 03:22 | Press Enter. |
| 03:24 | Type chmod plus +x nested-(Hyphen)for dot sh |
| 03:32 | Press Enter. |
| 03:34 | Type dot slash nested-(Hyphen)for dot sh |
| 03:39 | Press Enter. |
| 03:40 | The output is displayed. It shows Files in test directory. Files in test2 directory.And files in test3 directory. |
| 03:52 | This brings us to the end of this tutorial. |
| 03:56 | Let us summarize.In this tutorial we learnt,Nested for loop |
| 04:02 | As an assignment |
| 04:04 | Retype nested (hyphen)-for dot sh bash script using nested while loop. |
| 04:11 | Save your program with the name 'nested-(hyphen)while Dot sh' |
| 04:17 | Watch the video available at the link shown below.It summarises the Spoken Tutorial project |
| 04:23 | If you do not have good bandwidth, you can download and watch it |
| 04:28 | The Spoken Tutorial Project Team Conducts workshops using spoken tutorials Gives certificates to those who pass an online test |
| 04:37 | For more details, please write to contact@spoken-tutorial.org |
| 04:45 | Spoken Tutorial Project is a part of the Talk to a Teacher project It is supported by the National Mission on Education through ICT, MHRD, Government of India |
| 04:57 | More information on this Mission is available at: http://spoken-tutorial.org\NMEICT-Intro |
| 05:03 | The script has been contributed by FOSSEE and Spoken-tutorial team. |
| 05:08 | This is Ashwini Patil from IIT Bombay.Thank You for joining. |