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How to generate 256-bit random hex strings in MacOS

The command openssl gives us everything we need. If you run openssl rand -hex 32 you will have an output like this: openssl rand -hex 32 fe2b27f8d12cc51729c6fcf43c8316b156eb86d539330ab8eb9b5641a5569df0 But what happens if we need more than one, say 20. We'll need to run seq 20 | xargs -n1 -I{} openssl rand -hex

Ethernet

Ethernet

What is Ethernet? Ethernet is the most common wired networking technology used in homes, offices, and data centers. It allows computers and other devices to communicate over a local area network (LAN) using cables and standardized protocols. Ethernet Cable Wiring Standards Ethernet cables use twisted pairs of wires to carry

IEEE-754

IEEE-754

Floating Point Made Simple! The IEEE-754 standard defines how computers represent floating point numbers — that is, numbers with decimals like 3.14 or -0.001. It helps ensure that all systems (computers, languages, CPUs) store and calculate with floating point numbers consistently. Why Do We Need IEEE-754? Computers use binary

AES GCM in .NET 8 (.csx script)

AES GCM in .NET 8 (.csx script)

Well, sooner or later, I would need a way to encrypt things, a safe way, therefore here I leave the code for AES GCM string encryption with .NET 8. I assume you already have .NET 8 installed as well as dotnet-script. #!/usr/bin/env dotnet-script /* ====================================================================== + AES-GCM (Galois/Counter Mode) -

AES Encryption Decryption Tool in .NET 8 (Console App)

AES Encryption Decryption Tool in .NET 8 (Console App)

Here is the code! copy it and paste it inside a file (say AESFileEncryptDecrypt.csx) and then run it with dotnet-script AESFileEncryptDecrypt.csx. I am assuming that you already have dotnet-script tool installed globally in your computer as well as .NET 8 SDK. In case you don't, you can install

JWE Generation & Verification in .NET 6

JWE Generation & Verification in .NET 6

This code is the result of a chat session with AI using codegemma:7b model. Generate JWE public static string GenerateJweToken(string issuer, string audience, SymmetricSecurityKey key, SigningCredentials credentials) { var claims = new[] { new Claim(JwtRegisteredClaimNames.Sub, "user_id"), new Claim(JwtRegisteredClaimNames.Name, "John Doe"), new Claim(JwtRegisteredClaimNames.Email, "john.doe@

JWT Generation & Verification with HMAC SHA-256 Signature in .NET 6

JWT Generation & Verification with HMAC SHA-256 Signature in .NET 6

This code is the result of a chat session with AI using deepseek-coder-v2-latest model. using System; using System.IdentityModel.Tokens.Jwt; using System.Security.Claims; using System.Text; using Microsoft.IdentityModel.Tokens; class Program { static void Main(string[] args) { // Define the security key and algorithm to sign the token var

AES-256 Encryption / Decryption with Key in environment variable

AES-256 Encryption / Decryption with Key in environment variable

This is a very simple AES-256 string encryption/decryption program written in Node.JS using the built-in crypto library. // aes256.js const crypto = require('crypto'); const ENCODING = 'base64'; const KEY = process.env.MY_SECRET_KEY; function verifyKey() { if (!KEY) { throw new Error('MY_SECRET_KEY was not found!'); } } function

.NET Environment Setup in MacOS

.NET Environment Setup in MacOS

Recently I've been assigned a task in which I will need to develop software using Microsoft .NET Framework. The only problem is that currently I am using a MacBook Pro so here is what I did to get from 0 to hero. brew install --cask dotnet-sdk Your console output may

How to create menu in Node.JS

How to create menu in Node.JS

From the times of my Borland C programming where we had a fixed-width terminal that never changed size I had come up with the following code in Node.JS to now make it dynamically adjustable. The following code is just a skeleton and may be adjusted to your needs. const

iTerm2 Installation and Configuration in MacOS

iTerm2 Installation and Configuration in MacOS

1. Install it brew install --cask iterm2 2. Run the following commands: terminator@skynet ~ % echo $0 -zsh terminator@skynet ~ % which zsh /bin/zsh terminator@skynet ~ % chsh -s $(which zsh) Changing shell for hperez. Password for hperez: chsh: no changes made 3. Configuration Go to https://iterm2colorschemes.com and search for

Step-by-Step Guide to Resolve Merge Conflicts in GitLab

Step-by-Step Guide to Resolve Merge Conflicts in GitLab

Resolving merge conflicts can be a bit tricky. This guide addresses the scenario where you created a merge request to merge your-feature-branch into develop but GitLab tells you that the merge is blocked due to conflicts that you can't see in your local copy of the code. Here’s a

How to "Open in Terminal" from any folder in MacOS

How to "Open in Terminal" from any folder in MacOS

So, here's the situation: For us Fedora 40 users, we are used to right-click inside any folder and select the Open in terminal option that will launch the terminal and swith to the same folder we right-clicked on. Now, the problem is: In MacOS that is not really an option

Things to do after getting a new MacBook Pro (Apple Silicon)

Things to do after getting a new MacBook Pro (Apple Silicon)

If you own a MacBook Pro for your job then check the enrollment process with your company first and any rules they have in place. 1. Install Homebrew /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)" 2. Install Rectangle App Get if from here.