Alright ! Let’s talk about using libraries in our code. Libraries are pre-written pieces of software that can help us save time and effort by providing common functionality without having to reinvent the wheel every time we need it. In this tutorial, we will show you how to use a library at compile time.
First, let’s download and extract our desired library using these simple commands:
# This script downloads and extracts a desired library from a specified URL using wget and tar commands.
# First, we use wget to download the library from the given URL and save it as a compressed file.
wget https://example.com/library_name -qO- | grep 'https.*\.tar\.gz$' | cut -d'"' -f2 | xargs wget -q -c
# Then, we use grep to filter the output and only keep the URL that ends with .tar.gz, which is the compressed file we want.
# Next, we use cut to extract the URL from the output and save it as a variable.
# Finally, we use xargs to pass the URL as an argument to another wget command, which downloads the compressed file and saves it in the current directory.
# Now, we use tar to extract the downloaded compressed file.
tar -zxf library_name*.tar.gz
# Lastly, we use rm to remove the downloaded compressed file, as it is no longer needed.
rm *.tar.gz
This will download the latest version of our desired library from its website and extract it into a folder named after its name (in this case, “library_name”).
Now that we have our library files in place, let’s link them to our project. This is where the magic happens! We can use a compiler object called `set_libraries` to include all the libraries mentioned in its list of strings (libnames). Here’s an example:
// This script is used to demonstrate how to link library files to a project using a compiler object called `set_libraries`.
// First, we include the necessary header file from our library (replace "library_name" and "header_file" with the actual names):
#include <iostream>
#include "library_name/header_file.h"
// Next, we define our main function:
int main() {
// We create an object of the class "Function" from our library:
LibraryName::Function function;
// We call the function and store the result in a variable:
int result = function();
// We print the result to the console:
std::cout << "Result: " << result << std::endl;
// We return 0 to indicate successful execution of the program:
return 0;
}
In this example, we are using the `set_libraries` compiler object to include our desired library (library_name) in our project. We have also included its header file (header_file.h) so that we can use its functions and classes within our code.
And there you have it! Using a library at compile time is not rocket science, but it can make your code go from “meh” to “wowza!” Give it a try and let us know how it goes in the comments below.