# COMMAND LINE

# 1 - What is CMD LINE -
The command line, also called the Windows command line, command screen, or text interface, is a user interface that is navigated by typing commands at prompts, instead of using the mouse. a command line only uses a keyboard to navigate by entering commands and does not utilize a mouse for navigating.
Advantages:
-Much faster. No GUI overhead (unless we are talking pseudo-terminals).

-They don't need memorization. If you forgot a command option, just run it with -h, —help, or man/info it.

-For complex tasks, the command line can be scripted to automate things.

-To run sequence of commands as a single command.

# 2 - Why might you want to customize it?-

- improve your workflow significantly and help you write more code.
- make it looks good.
- tasks more efficient, and even faster.
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# 3 - CMD LINE Custimization

You can customise you CMD Line in a number of ways, including the following:

## Change Prompt (PS1 varible):
- You can change your prompt by altering the PS1 varible in the comand line with the following code

`PS1="new prompt"`

- So `PS1="Jake's Prompt >"`, would result in:


- As an example, `PS1="\w"` makes the prompt the current working directory, for example:


- You can also add a bunch of other useful things to the prompt, such as the things listed below.


- For example, to add a your user name followed by a working 24hr clock you could simply type `PS1=" \u \T : "`


### Changing Color:
- We can change the color of elements of the terminal, the possible colors and their codes are below.


-The need to enclose the color in ``\[`` and ``\]`` so that the terminal can read it, so the code for __blue__ will look like this:

`\[\e[34m\]`

- We can then turn elements into that color by including them, for example in the prompt/PS1 as follows:


- To stop everything going the same color, you need to include `\e[00m\]` at the end of the prompt, as follows:

`PS1="\[\e[34m\] BLUE PROMPT ONLY: \e[00m\]"`


- It is also possible to add emojis and multiple colours to the command line, such as below (video link included):

[--> Video Guide to making a pretty Command Line <--](https://www.youtube.com/watch?v=C92eaq_bZR8)


## Saving your changes to Profile
- The above will only give you temporary changes to the terminal, so in order to make these permanant you need to add them to your **Profile**.

- In order to do this you need to find `.bashrc file` located in your home directory (type `ll` at home screen to view the files, then `code .bashrc` in terminal to open in code editor)

- You then need to `export` the PS1 edit into the Profile file and save it, to ensure eveythime you open the terminal the changes are there:

`export PS1="#####"`


### GIT BRANCH
- You can also add your current Git Branch to your command prompt, but this requires including a new function within you **bashrc** file before you are able to run the code.

- copy and paste the following function into your bashrc file:

`git_branch() {
git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/(\1)/'
}`

- Then this will then allow you to include `\$(git_branch)` is your PS1 export to add the current git hub branch to the prompt (branch is called **"updateStyle"** in this case, and is only active when you are in a folder tracked by GitHub):

`PS1="\[\e[34m\] BLUE PROMPT ONLY: \e[00m\] \$(git_branch)"`

Branch

Master

- Please see following guide for more info: [Link to Git Branch Guide](https://www.shellhacks.com/show-git-branch-terminal-command-prompt/)

# Package Manager

You can also install a **Package Manager**
- A Package manager is
`Package management is a method of installing and maintaining (which includes updating and probably removing as well) software on the system.`

- This allows you to
`To Install Software`

You can install via:-
### The APT is the tool
- apt-get and it’s the easiest way to
install files/Softwares packages.

sudo apt-get install ${packagename}

- To remove/uninstall any software, just use remove

sudo apt-get remove ${packagename}

- The software packages are somewhere in the online repositoies, APT handles a local database on the user’s hard drive that contains informations about the available packages and where they are located.

- to get the all newly uploaded packages on the repositories, user need to update APT regularly.
To update APT database:

sudo apt-get update

link with more info
https://www.howtogeek.com/63997/how-to-install-programs-in-ubuntu-in-the-command-line/

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