DEV Community: Anthony

5 Useful Linux Commands to make you look like a Pro

Anthony — Tue, 22 Nov 2022 19:17:58 +0000

The command line can be an intimidating and scary black screen when first introduced to beginners. Where are the fancy buttons? The colors? How can I move files? Where is my mouse!?

These 5 Linux Commands will give you a better handle of the command line and will make you look like a pro.

1. "`cp`"

The cp command stands for "copy" and the syntax of the cp command works like this:

$ cp [OPTIONS] SOURCE DESTINATION

Where the SOURCE is copied over to DESTINATION, you can also have multiple SOURCE files, so that you can copy over multiple files to DESTINATION. A useful flag that you may end up using a lot is the -R, -r, or --recursive command, which allows you to cp entire directories recursively. For example:

2. "`mv`"

The mv command otherwise known as "move" will move files wherever you want them to go, similar to the cp command, but instead of leaving a copy the entire file or directory will get moved to the DESTINATION. Also, in the man docs mv it shows, mv - move (rename) files. So, not only can you move files, but by using the mv command like this:

$ mv [FILE] [RENAMED]

A useful flag to understand what is going on while using the mv command is the -v command, which stands for verbose. When you use the mv command, use a -v before your SOURCE input to show a more detailed view of what the mv command is doing. For example:

3. "`|`"

The | command, aka the "pipe" command is used to combine two or more commands where the first command will be an input for the second command. (And so on so forth) Seeing the "pipe" in action makes it easier to understand.

In this block of code, the contents of cat are shown, then you would use the | command to use the contents of file.txt and run the command sort on them, which alphabetically sorts the contents of file.txt and displays those results on the console.

4. `>`

The right-angle bracket is a way to transform and push data in your terminal from one place to another. Just like the example from the pipe command you can store the data of the sorted file.txt to another file called sorted_file.txt, so:

First, you sorted checked the file contents of file.txt and then you used the pipe command along with the sort command. From above, you saw that this displayed the contents of file.txt but alphabetically sorted, now with the > command, you take those contents of the alphabetically sorted file and put that data into a new file called sorted_file.txt. Neat right?

The > and | may not be super useful by themselves, but when used with other commands they are very powerful tools that you can use to your advantage.

5. `grep`

From the man docs grep prints lines that match a pattern that you specify. The usage is as follows:

$ grep [OPTION...] PATTERNS [FILE...]

A simple usage for the grep command could be to find all lines that have an "a" in a file. For example:

You can extend the grep command to look for certain files, combining the grep command with the | command:

Using these commands in unison with each other will give you a better grasp at the Linux terminal, and make you look like a pro to your friends and co-workers.

BONUS: `tree`

The tree command is not a preinstalled command available in Linux, although, it is a nifty tool that can help you find files in your system. To install tree run

$ sudo apt install tree

For Ubuntu systems, although other systems may use different package managers. tree lists contents of a directory in a tree-like format. For basic usage you could run

$ tree folder

For example:

Then, using your new founded knowledge of the "pipe" command and "grep" you can filter and find specific files that you want, for example, searching for all .cpp files.

$ tree labs | grep .cpp

Hope you found this useful!

Customize Your Terminal with Oh My Zsh

Anthony — Sun, 13 Nov 2022 02:59:46 +0000

If you feel like your terminal has a boring, unattractive, and bland style. Sort of like this one:

You may want to consider upgrading the look of your terminal to something vibrant and colorful.

Oh My Zsh

Oh My Zsh "is an open source, community driven framework for managing your Zsh configuration." Source

Oh My Zsh comes with a ton of custom themes that you can include in your terminal, along with 275+ plugins such as the "git" plugin (which comes in preinstalled) that you can use to individualize your terminal experience. Not to mention Oh My Zsh comes with a vibrant open-source community where you can post issues. They even have their own T-Shirts! Cool!
Link to their Github

How to Get Started

To start, you need to make sure that you zsh installed, to insure you have zsh installed you can simply run:

$ zsh --version

in your terminal. If you get a version number back, great! If not you can run:

$ apt install zsh

Assuming your running Ubuntu, the process may be different depending on what Distro you have installed on your system.

Now that you have zsh installed, to install Oh My Zsh you can run:
(with curl)

sh -c "$(curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"

(with wget)

sh -c "$(wget -O- https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"

(with fetch)

sh -c "$(fetch -o - https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"

Once you have installed Oh My Zsh, you may need to restart/reopen your terminal for the changes to take effect.

Customizing Your Terminal

There is a link on Oh My Zsh Github which has a list of themes you can customize your terminal with. Here
As soon as you have found a theme you like you need to edit your .zshrc file in order to make any changes.
For example, if you wanted the agnoster theme:

You would need to edit the .zshrc file, use any text editor you like. (Although, only REAL programmers use vim)

Change the quotations in ZSH_THEME into agnoster, or to whatever theme you like!
After you changed the theme, save the file, and you may need to restart/reopen your terminal to see the changes in effect.

What a cool looking terminal!

Hope this helped you, and made your terminal more snazzy! 😎😎😎

(Cover Photo and agnoster Photo from Oh My Zsh Github)

The Reality of Imposter Syndrome

Anthony — Thu, 03 Nov 2022 01:45:04 +0000

Imposter syndrome is defined as “the psychological occurrence in which an individual doubts their skills, talents, or accomplishments and has a persistent internalized fear of being exposed as a fraud”
(Source)

As programmers, Computer Scientists, coders, students, and professionals there are times when you feel like your accomplishments may have been a stroke of luck or just by coincidence. There have been times when learning new concepts or technologies when I have just felt lost and confused. Just leading to a slew of negative emotions such as,
__
“If I can’t figure this out I’m not a real programmer”
Or
“How did I get this far, there's no way I’ll be able to continue.”
__

Similarly, you may feel like this when applying to jobs,
__
“I’m not smart enough, this job won’t accept me.”
Or
“There is no way I am going to get [x] internship”
__

The first factor to recognize is that

You are NOT alone

Everyone at some point in their life, even if they aren't programmers, has felt some sort of Imposter Syndrome in their life. Recognizing that you are not the first person to feel like a fraud, (and for sure will not be the last) is the first step in overcoming feelings of insecurity.

Document Your Progress

When I started learning about programming I was in high-school going through the freecodecamp.org Javascript Algorithms and Data Structures Certification along with some Web Design. Learning how to make HTML, CSS, and JS files was something that seemed like such a big goal when I was working on it. After years of putting in effort along with making my own personal projects along the way I have realized that I have come a long way. Being able to see your progress in a tangible way will make recognizing your growth more easier. You can use version control software such as Git/Github in order to track your progress along your coding journey. There have been projects that I have worked on in the past that I think are awful now, looking back on it there are myriads of lines of code I would change. But knowing that you would have made your code better now is realizing that you have grown as a programmer since then.

Join a Community

Whether that be through your work, a discord server, a group of friends in school, or even through open source contributions join a supportive community that will help you along your coding journey. Having a community of like minded people will help you grow as a programmer and as a learner. To be able to bounce ideas off of your community will improve your communication skills and will help you overcome feelings of being alone with your problems. If you have a problem, chances are someone has also had that same exact problem too.

Don't Compare Yourself with Others

There is always a bigger fish in the sea, so they say. Track and field coaches always emphasize one thing to their athletes. To never look behind them or at other contestants. Always look at the track in front of you, and don't worry about the other athletes. This philosophy is similar in many aspects of life, and is crucial in overcoming Imposter Syndrome. Compare yourself to the person you were yesterday, if you learned something new or became a better programmer by 0.000001%, that is something to proud of.

Please leave your thoughts in the comments below ;)

Hope this helped you!🔥🔥🔥

cd Back Multiple Directories in One Line

Anthony — Thu, 27 Oct 2022 21:16:25 +0000

Having to cd.. over and over again in sub directories can be a tedious and annoying thing to do. Although it may be cool when you can quickly navigate through multiple directories it can be really annoying if you are trying to be efficient in your terminal.

Every time you open up a new session if your terminal there are custom-loaded preferences that are loaded into that session, whether that be for programs you have or for your bash environment. For example, every time I open up Vim in my terminal I have the :set number property to always be on, so I can see what line I am on or want to go to, for example:

Creating Your Own Custom Bash Command File

So in order to make your own custom commands you should make your own Custom Bash Commands File and you can call this whatever you want. As long as it is memorable, so tomato_soup.sh would not be a good file name. 😉
- Also, since you don’t want to see this file every time you ls in your system. You should preface the name of your file with a . so that it is a hidden file in your system. If you wanted to view the hidden files in the current directory you are in you can use the ls command along with the -a or the --all flag, which just means list all the files in the current working directory.
Once you created your own file with the touch command such as touch .custom_bash.sh you can use Vim or Nano to edit the file and make changes to it. (Use Vim its cooler 😉)
Now that you are inside the file you created, use this code in order to cd.. back multiple directories.

#!/bin/bash

function cd_up(){
    cd $(printf "%0.s../" $(seq 1 $1));
}

alias 'cd..'='cd_up'

Place that code anywhere inside your custom file and remember to save before you exit.

After you have saved we need to test out the command to make sure it works.
Use the source command along with the custom bash file you made so, souce ~/.custom_bashcommands.sh

Then cd into some subdirectories and try cd.. 2 to see if it works or not.

Although, using this method you would need to run the source command every time you open up a new terminal instance, to avoid this we can link our custom bash file into our bash profile so that every time we open up a new terminal our custom commands are preloaded.

To do this open your .bash_profile file and place the preceding command anywhere in the file,
so in our case you would put souce ~./custom_bashcommands.sh into .bash_profile. Exit .bash_profile and close and reopen your terminal to see changes.

DEMO:

Hope this was useful to you!

7 Quick Tips from Google's Resume Workshop

Anthony — Tue, 25 Oct 2022 18:12:41 +0000

During the summer I was able to partake in a program called CSSI, (Computer Science Summer Institution) hosted by Google. It was a four-week boot camp/internship where aspiring Computer Science students worked with Google engineers/employees to learn and make HTML, CSS, and Javascript programs. CSSI is usually hosted in Google headquarters, but due to the pandemic, it was hosted online for most people. Although there were some programs with Universities where it was done in person. The program was every day, for about 3-5 hours, depending on how much work you wanted to put into the program. There were advantageous opportunities such as resume workshops, and my favorite opportunity, a Google Techincal Mock Interview.

Although the feedback given to me may be catered to me since I am still a student studying Computer Science, some of the feedback I was given may be helpful to you. Some of this feedback you may already know, whereas some of it may be new to you, regardless I hope you take something useful from the feedback I was given.

What I learned from Google’s Resume Workshop

The most important things should be on the top of the page
- Don’t just list out skills or jobs as they come to your head, carefully craft your resume so that the most important things are the things that pop on your resume.
If you are a student applying to Google put relevant coursework in your resume.
- I doubt Google will really care that you took let's say a History class if you are applying for a technical position. Although, if you were applying for more of an HR position, maybe relevant coursework may be Psychology.
I was told that some include their LinkedIn profiles, this is just a personal choice and not a deciding factor in the resume review process
- Although, I do prefer to use LinkedIn since they have their own resume builder, rather than using some shoddy “free” resume builder online.
Try avoiding putting too much information on your resume
- A cluttered resume is no good either, put what is needed, too much information on your resume makes its convoluted and much harder to read.
Follow the STAR Method, Situation, Task, Action, and Result
- Provide a Situation, which most likely entails a problem, a Task that is something you assigned to yourself or were assigned, an Action so something you DID, and a Result which is the outcome of how you solved the problem.
Follow the DRY Principle
- Don’t Repeat Yourself, if you said you worked on a certain project, don’t bring up that project again.
Make careful use of the tenses you use in your resume
- For things you have already done keep it in the past tense.
- For things you are doing keep it in the present tense ### Bonus! KISS Method
- Keep it Simple Stupid! You don’t need crazy graphics or fancy-looking font. (If you use Comic Sans so help me God.)
- Logos of the companies or the places you worked at are cool, but they are not really needed, keep it consistent.

Hope this helped you! ✌️ ✌️ ✌️ ✌️

5 VSCode extensions every programmer needs

Anthony — Fri, 21 Oct 2022 22:53:00 +0000

VSCode extensions enhance the productivity of your environment, anywhere to language support, formatters, and debuggers, they all assist your workspace ecosystem.

1. Prettier - Code Formatter

Prettier takes your code and parses it into a nice-looking block of code.

2. Python

The Python extension comes with Intellisense, Linting, Debugging, Pylance, Jupyter Notebook, and so much more. A must have for Python developers using VSCode.

3. SSH FS / SSH

If you need to connect to some other host computer SSH along with SSH FS are great VSCode extensions to make your life easier.

4. Edit CSV

If you need to make adjustments to a CSV table quickly and effectively, Edit CSV is for you.

(Gif from Extension Page)

5. Auto Rename Tag

If you work with React JS or anything similar you may know how annoying it is to keep renaming JSX or HTML tags for both the opening and closing tags. Be annoyed no more!

BONUS: Vim

This VSCode extension emulates Vim for Visual Studio Code, Vim increases the productivity by emphasizing the use of the keyboard while programming. (Only real programmers use Vim)

Happy Hacking!

Interning for an AP Computer Science Class

Anthony — Fri, 21 Oct 2022 03:51:54 +0000

I had the amazing opportunity to intern for an AP (Advanced Placement) Computer Science class in high school, more specifically AP Computer Science Principles. I was a senior during that time, taking that same class last year and thought it would be a great opportunity to help other students start their journeys in Computer Science.

For those interested, the class covered basic HTML, CSS, and JS topics for the first semester, then during the second semester the class shifted gears into teaching Python, later using some APIs during the final weeks. Such as the Twitter API.

The most important takeaway from my internship experience was that:

It is ok to say "I don't know"

During the first semester I would get flustered and try to make up some shoddy solution if I didn't know the answer to one of the students' questions. I would feel embarrassed because I thought I should have known the answer to all their questions, and somehow be some kind of Computer Science God, whereas this was just not the case.

I learned how to be comfortable with not knowing something, and instead of saying,

"Uhh, yea the mainframe is just broken I guess, have you tried restarting your computer?"

I'm more comfortable saying,

"Hey, I don't know. Let's debug it together and find out why."

That way, I was way more relatable to the students, they wouldn't be afraid to ask me questions, and at the end of the day I ended up learning alongside them.

Happy Hacking!

What is Command Injection, and how to protect yourself against it?

Anthony — Tue, 18 Oct 2022 19:15:37 +0000

Command injection is a cyber-attack that involves executing commands on another person's host operating system. This could include removing files and changing data on the host computer. This type of attack happens when the programmer does not use enough input validation to check if the input is malicious or not.

For example, in Python you can code:

import os

domain_name = input()

os.system('ping ' + domain_name)

Then, when I run this in my computer, I can input google.com as the domain_name, such as:

As you can see, you get a response back from Google!

Although, someone not as nice as me or you may type out something different when prompted for input. Let's say you want to just echo what the user said back to us from the command line.

You would just replace the ping in the os.system with
os.system('echo ' + input)

But this time, lets add ; ls after whatever you want to echo

As you can see, we get the files in the current working directory, which happens to be example.py. This is bad.

You can even take it a step further and use the rm command to remove a file on your system such as:
hello; rm example.py

As you can see the file is now gone from your computer. This can lead to a slew of security issues if left unchecked. To combat this (in Python specifically) we can use the call method from the subprocess module. Such as

from subprocess import call

user_input = input()

call(["echo", user_input])

The call function will make sure that only a single command will be run.

There are language equivalents for the example in Python above.
Be safe!
(Anime CS Girls)