Tutorial by Examples: e

Pointer addition Given a pointer and a scalar type N, evaluates into a pointer to the Nth element of the pointed-to type that directly succeeds the pointed-to object in memory. int arr[] = {1, 2, 3, 4, 5}; printf("*(arr + 3) = %i\n", *(arr + 3)); /* Outputs "4", arr's fourth e...

The member access operators (dot . and arrow ->) are used to access a member of a struct. Member of object Evaluates into the lvalue denoting the object that is a member of the accessed object. struct MyStruct { int x; int y; }; struct MyStruct myObject; myObject.x = 42; myObj...

The first operand must be a function pointer (a function designator is also acceptable because it will be converted to a pointer to the function), identifying the function to call, and all other operands, if any, are collectively known as the function call's arguments. Evaluates into the return valu...

The X-macro approach can be generalized a bit by making the name of the "X" macro an argument of the master macro. This has the advantages of helping to avoid macro name collisions and of allowing use of a general-purpose macro as the "X" macro. As always with X macros, the mas...

The git check-ignore command reports on files ignored by Git. You can pass filenames on the command line, and git check-ignore will list the filenames that are ignored. For example: $ cat .gitignore *.o $ git check-ignore example.o Readme.md example.o Here, only *.o files are defined in .git...

There are three ways of creating a new branch feature which tracks the remote branch origin/feature: git checkout --track -b feature origin/feature, git checkout -t origin/feature, git checkout feature - assuming that there is no local feature branch and there is only one remote with the featur...

The class name selector select all elements with the targeted class name. For example, the class name .warning would select the following <div> element: <div class="warning"> <p>This would be some warning copy.</p> </div> You can also combine class n...

ID selectors select DOM elements with the targeted ID. To select an element by a specific ID in CSS, the # prefix is used. For example, the following HTML div element… <div id="exampleID"> <p>Example</p> </div> …can be selected by #exampleID in CSS as sho...

URLs for links can be specified later in the document. Markdown [Text1][1] will link to the first link, and [Text2][2] to the second. You [can reuse][1] names, and give longer names [like this one][a link]. You can also link text [like this] without giving the reference an explicit name. [1]:...

Text prefixed with one to six pound signs (hash symbols, #) becomes a header <h1> through <h6>, according to how many pound signs were used. # This is a first-level (`<h1>`) header ## This is a second-level (`<h2>`) header ### And so on. This is a first-level (<h1&...

Characters for bulleted lists: * Asterisks + Plus signs - Minus signs Characters for bulleted lists: Asterisks Plus signs Minus signs Please note: For the best results you have to use the same character because as you can see in the example below different signs make the list ...

1. Lists can be nested * Four spaces - Eight spaces + Twelve spaces 2. And back Lists can be nested Four spaces Eight spaces Twelve spaces And back

Pseudo-classes are keywords which allow selection based on information that lies outside of the document tree or that cannot be expressed by other selectors or combinators. This information can be associated to a certain state (state and dynamic pseudo-classes), to locations (structural and target p...

In this example we are going to plot multiple lines onto a single axis. Additionally, we choose a different appearance for the lines and create a legend. % create sample data x = linspace(-2,2,100); % 100 linearly spaced points from -2 to 2 y1 = x.^2; y2 = 2*x.^2; y3 = 4*x.^2; ...

Creating an empty table is as simple as this: local empty_table = {} You can also create a table in the form of a simple array: local numeric_table = { "Eve", "Jim", "Peter" } -- numeric_table[1] is automatically "Eve", numeric_table[2] is "Ji...

A database snapshot is a read-only, static view of a SQL Server database (the source database). It is similar to backup, but it is available as any other database so client can query snapshot database. CREATE DATABASE MyDatabase_morning -- name of the snapshot ON ( NAME=MyDatabase_data, -- l...

If data in a source database becomes damaged or some wrong data is written into database, in some cases, reverting the database to a database snapshot that predates the damage might be an appropriate alternative to restoring the database from a backup. RESTORE DATABASE MYDATABASE FROM DATABASE_SNAP...

Here's the 'bare minimum' Arduino sketch. This can be loaded into the Arduino IDE by choosing File > Examples > 01. Basics > Bare Minimum. void setup() { // put your setup code here, to run once } void loop() { // put your main code here, to run repeatedly } Code in the setup...

docker run hello-world This will fetch the latest hello-world image from the Docker Hub (if you don't already have it), create a new container, and run it. You should see a message stating that your installation appears to be working correctly.

docker run docker/whalesay cowsay 'Hello, StackExchange!' This command tells Docker to create a container from the docker/whalesay image and run the command cowsay 'Hello, StackExchange!' in it. It should print a picture of a whale saying Hello, StackExchange! to your terminal. If the entrypoin...