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In the previous post I talked about how C++ code gets compiled from its source files into an application exe or library. This post will demonstrate setting up a C++ compiler on the Raspberry Pi. More specifically, using g++ which is the C++ compiler in the GNU Compiler Collection (GCC).

Installing G++

The first thing you want to do is log into your Pi via SSH from your main computer. We will install GCC via the apt-get package manager. Open up the terminal and enter the following:

> sudo apt-get install g++

After a few seconds the process will finish, typing “g++” into the terminal should yield the following:

g++: fatal error: no input files compilation terminated

Testing the Compiler

Now that we have the compiler installed, let’s create a simple C++ program. Using your terminal, create a file called “hello.cpp” with the following command:

> touch hello.cpp

The touch command will create the file if it doesn’t exist, it will also leave the file untouched if it did exist in the first place.

With our file created, let’s enter some simple C++ code. I won’t go over the code here, as it’s only to test the compiler.

Open up the file in your favourite editor (I suggest setting up Visual Studio Code for use with your Pi) and enter the following few lines of code:

#include <stdio.h> int main(int argc, char** argv) { printf("Hello, World!

"); return 0; } C++ Hello World Example

After saving the file, we must run it through the compiler. You will see in the next tutorial, we will abstract this process using CMAKE, but for the purpose of this tutorial we will pass the file straight to g++ via the terminal/command line.

The g++ CLI requires two parts, the input file(s) to be compiled and the output file these source files will be compiled into. In our case, we have one file to go in and one file to come out (an application executable). The command to do this is:

> g++ hello.cpp -o hello

After a few seconds you should notice another file called “hello” appear in the same directory (those of you using the terminal, you can list all files in the current directory by entering the “ls” command).

This file is the application executable that was compiled from the hello.cpp source file! You can execute it by entering the following:

> ./hello

If you see the words “Hello, World!” appear in your terminal, you can safely say that g++ is set up and ready to go!

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