Solving the Apache2 Error: Couldn't Grab Mutex with Certbot and SSL Certificates on Linux Ubuntu, Mint

The “Couldn’t grab mutex” error in Apache2 occurs when there is an issue related to file locking. This problem is often encountered when using Certbot and SSL certificates on Linux Ubuntu or Linux Mint. In this guide, we will focus on a solution to resolve this error.

Apache is a widely used...

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Methodology is a set of methods, techniques and procedures used to conduct research, solve a problem or achieve a specific objective. In other words, it is a systematic and organized approach to collecting, analyzing and interpreting information or data. The methodology can be applied in several areas, such as social...

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Programming paradigms are different approaches or styles of programming that provide a set of principles, concepts, and practices to solve computational problems. A programming paradigm defines the way in which a programmer structures and organizes code to build software applications.

There are several programming...

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I participated in a Business to Business (B2B) project, where I was part of the team that developed the backoffice platform, and another team developed Frontoffice (the e-commerce store). Each part of the platform - Back and Front Office needed to exchange data and it was necessary to establish a numbering rounding...

Back office and Front office are sets of activities and responsibilities in managing a business, and can be performed by teams of their own or outsourced in companies. In the context of software systems and applications, it is possible to adapt the service of solutions on different platforms, which interact with each...

If you want to set up the Best environment for software development in Linux Mint (or Ubuntu and other Debian based distros), this is the right article for this.

Every software developer organizes their development environment for programming using a mix of technologies and tools to use to program, improve productivity...

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By executing ESLINT in a JavaScript code, Nodejs or Expressjs, we can find the error “unexpected string concatenation” or “Unexpeted String Concatenation”.

This lint points to a possible code that manipulates string concatenation, which was written in order to result in a difficult reading....

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Where to find open data for statistical analyzes, seed databases with initial data or even create auxiliary tables for certain business areas? The developer community works hard to create repositories that offer data to meet these needs, how about checking and contributing to these repositories.

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A quick and straightforward tutorial that demonstrates how to generate random numbers in C language.

You can use the same functions to work with C++.

The motivation came from the need of my programming students, especially from courses not directly linked with computer science, such as those of Electrical Engineering....