Use a C library in Swift on Linux

Question

I know how to access C libraries in Swift using Xcode on Mac OS, and I know about import Glibc on Linux, but how can I use a C library like OpenGL with Swift on Linux?

Answer 1

Use a System Module to import the OpenGL header file: https://github.com/apple/swift-package-manager/blob/master/Documentation/SystemModules.md

Assuming you have a directory layout like:

COpenGL/
  Package.swift
  module.modulemap
  .git/

YourApp/
  Package.swift
  main.swift
  .git/

the COpenGL/module.modulemap file will look something like:

module COpenGL [system] {
    header "/usr/include/gl/gl.h"
    link "gl"
    export *
}

This has to be created in a separate git repo, with a version tag:

touch Package.swift
git init
git add .
git commit -m "Initial Commit"
git tag 1.0.0

Then declare it as a dependency in YourApp/Package.swift file

import PackageDescription

let package = Package(
    dependencies: [
        .Package(url: "../COpenGL", majorVersion: 1)
    ]
) 

Then in your main.swift file you can import it:

import COpenGL
// use opengl calls here...