Gain insights into the command-line interface, delve into navigating file systems, creating scripts, and automating tasks to enhance productivity and control your computer efficiently.

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ubuntu.tar.gz

Python job

ncjob

In this course, you will get the chance to explore the command-line interface (CLI), starting with basics like navigating file systems and working with directories and files. Then, you will use those building blocks to tackle more advanced features and tasks within the CLI. You will also learn to turn basic commands into executable scripts and easily automate common tasks. This course will empower you to put the interface to work, take complete control of your computer, and hack your way to productivity.

Harnessing the Power of the Command-Line Interface

One of the best things about automation is that you can put in a little extra work up front and get a lot of reward out of that work down the road.
# Using bash for automation
A typical website has a home page, at least one style sheet, a folder for images, and, most likely, some JavaScript files. So, let’s use Bash to automate that. We’ll have the script create a root directory for the website, an `index.html` file, a `scripts` directory, an `images` directory, and a `stylesheets` directory. And we’ll drop a `style.css` file in the `stylesheets` directory for good measure:


# The script

Using what we learned in [Working with Files and Directories](https://www.educative.io/courses/harnessing-power-command-line-interface/creating-files), we can probably write this script already. Our first approach might look like this:

```bash
mkdir -p mysite/{images,scripts,styles}
touch mysite/styles/style.css
cat << 'EOF' > mysite/index.html 
<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <title>My Website</title>
    <link rel="stylesheet" href="styles/style.css">
  </head>
  <body>
  </body>
</html>
EOF
```

That would work quite well, but we can make it even more flexible using variables so that we aren’t repeating the website throughout the script. This’ll also make it easier to change the directory’s name later, which we’ll do shortly. Let’s create the file `new_site.sh` and make it executable:




```bash
touch new_site.sh
chmod +x new_site.sh
```

We add the following content to the file:
```bash
#!/usr/bin/env bash
set -e directory="mysite"
mkdir -p ${directory}/{images,scripts,styles} 
touch ${directory}/styles/style.css
cat << 'EOF' > ${directory}/index.html <!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <title>My Website</title>
    <link rel="stylesheet" href="styles/style.css">
  </head>
  <body>
  </body>
</html>
EOF
```

The script starts with the shebang line, followed by `set -e`, which tells Bash that it should exit as soon as some statement fails. Without this option, Bash will attempt to run every command, even if previous ones errored out.

It then initializes a variable called `directory` with the name of the directory it will create to hold the files for the site. In this case, it’s using a hardcoded value: `mysite`. It then uses the `directory` variable in the paths when it creates the directories and files. Remember that we have to prefix the variable name with the dollar sign. If we don’t, Bash will use the literal word “directory” instead of the variable’s value. And since we’re mixing it with other characters in a string, it’s best to use `${directory}` here instead of `$directory`.

Run the script:

```
./new_site.sh
```

We don’t see any output from the script unless we’ve made a typo when creating the script. But we can verify that it worked by using the `tree` command to view the `mysite` directory:

```
tree mysite
```
You can run the complete code on the terminal below for practice.
```bash
cat << "END" > new_site.sh
#!/usr/bin/env bash
directory="mysite"
mkdir -p ${directory}/{images,scripts,styles} 
touch ${directory}/styles/style.css
cat << 'EOF' > ${directory}/index.html 
<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <title>My Website</title>
    <link rel="stylesheet" href="styles/style.css">
  </head>
  <body>
  </body>
</html>
EOF
END
chmod +x new_site.sh
./new_site.sh
tree mysite
```



# The script

Using what we learned in [Working with Files and Directories](https://www.educative.io/courses/harnessing-power-command-line-interface/creating-files), we can probably write this script already. Our first approach might look like this:

```bash
mkdir -p mysite/{images,scripts,styles}
touch mysite/styles/style.css
cat << 'EOF' > mysite/index.html 
<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <title>My Website</title>
    <link rel="stylesheet" href="styles/style.css">
  </head>
  <body>
  </body>
</html>
EOF
```

That would work quite well, but we can make it even more flexible using variables so that we aren’t repeating the website throughout the script. This’ll also make it easier to change the directory’s name later, which we’ll do shortly. Let’s create the file `new_site.sh` and make it executable:




```bash
touch new_site.sh
chmod +x new_site.sh
```

We add the following content to the file:
```bash
#!/usr/bin/env bash
set -e directory="mysite"
mkdir -p ${directory}/{images,scripts,styles} 
touch ${directory}/styles/style.css
cat << 'EOF' > ${directory}/index.html <!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <title>My Website</title>
    <link rel="stylesheet" href="styles/style.css">
  </head>
  <body>
  </body>
</html>
EOF
```

The script starts with the shebang line, followed by `set -e`, which tells Bash that it should exit as soon as some statement fails. Without this option, Bash will attempt to run every command, even if previous ones errored out.

It then initializes a variable called `directory` with the name of the directory it will create to hold the files for the site. In this case, it’s using a hardcoded value: `mysite`. It then uses the `directory` variable in the paths when it creates the directories and files. Remember that we have to prefix the variable name with the dollar sign. If we don’t, Bash will use the literal word “directory” instead of the variable’s value. And since we’re mixing it with other characters in a string, it’s best to use `＄{directory}` here instead of `＄directory`.

Run the script:

```
./new_site.sh
```

We don’t see any output from the script unless we’ve made a typo when creating the script. But we can verify that it worked by using the `tree` command to view the `mysite` directory:

```
tree mysite
```
You can run the complete code on the terminal below for practice.
```bash
cat << "END" > new_site.sh
#!/usr/bin/env bash
directory="mysite"
mkdir -p ${directory}/{images,scripts,styles} 
touch ${directory}/styles/style.css
cat << 'EOF' > ${directory}/index.html 
<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <title>My Website</title>
    <link rel="stylesheet" href="styles/style.css">
  </head>
  <body>
  </body>
</html>
EOF
END
chmod +x new_site.sh
./new_site.sh
tree mysite
```



Learn how to automate file and directory creation.

Introduction

Creating an Ubuntu Virtual Machine with VirtualBox

Navigating the Filesystem

Working with Files and Directories

Streams Of Text

The Shell and Environment

Running and Managing Programs

Networking Tools

Automation

Additional Programs

Conclusion

Automating File and Directory Creation

Using bash for