Tutorial on Lorbic

Learn Dart Programming

Wed, 12 May 2021 16:28:00 +0530

Good Evening, Here are the Hands-on notes for Dart Programming Language. I created these notes when I was learning Dart Language. So, these notes might help you too. You can use these notes as a quick reference to Syntax and Demo. I’ve covered almost every fundamental concept of Dart in this article.

Photo by Birmingham Museums Trust

1. Basics

1.1 The Main Function

Every Dart program starts execution from main() functions.

Types of Pointers in C/C++

Wed, 12 May 2021 16:16:41 +0530

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Types of Pointers in C / C++

1. Null Pointer

It is a pointer pointing to nothing. NULL pointer points to the base address of the segment.

-EXAMPLE-

1int * ptr = (int) * 0;
2float * fptr = (float) * 0;
3double * dptr = (double) * 0;
4char * chptr = (char) * 0;

Other ways of initializing NULL pointer

1int * ptr = NULL;
2char * chptr = '\0';

NULL also means 0 in macro
c
1#define NULL 0

2. Dangling Pointer

A pointer pointing to the memory address of any variable (or object) which has been deleted from memory.
When a pointer points to a deleted memory address, the pointer is called as a dangling pointer.

Avoid Memory Leaks In C++

Tue, 04 May 2021 01:24:39 +0530

Instructions

Things You’ll Need

Proficiency in C++
C++ compiler
Debugger and other investigative software tools

Part 1

Understand the operator basics. The C++ operator new allocates heap memory. The delete operator frees heap memory. For every new, you should use a delete so that you free the same memory you allocated:

cpp

1char* str = new char [30]; // Allocate 30 bytes to house a string.
2delete [] str; // Clear those 30 bytes and make str point nowhere.

Part 2

Reallocate memory only if you’ve deleted. In the code below, str acquires a new address with the second allocation. The first address is lost irretrievably, and so are the 30 bytes that it pointed to. Now they’re impossible to free, and you have a memory leak:

Operators in Bash Shell Programming

Tue, 04 May 2021 01:16:10 +0530

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If you want to learn bash bash scripting please read this article.
Learn complete Linux bash (shell) scripting in one article

Operators help us perform various types of operations such as addition, multiplication etc.
There are following types of operators present in bash:

Arithmetic,
Relational,
Boolean,
File Test,
String Test

1. Arithmetic Operators

All the arithmetic operators present in bash are discussed below with examples.
These operators work with integers.

Access Wsl Filesystem From Windows 10 File Explorer

Tue, 04 May 2021 00:52:26 +0530

If you want to get Linux environment in your Windows system there are some solutions that provide the opportunity.
For example MYSYS, CYGWIN and a Virtual Machine (If you want complete linux machine) or Multiple Boot.
But some of them aren’t much powerful and some are resources hungry like Virtual Machine.
So, the solution is WSL (Windows Subsystem for Linux).
You can learn how to setup WSL from here.