How to Install Mono on Debian 10 Buster

Mono platform is used to develop and run cross-platform applications. It is open-source and free implementation by the Microsoft. This tutorial explains how to install Mono on Debian 10.

Prerequisites

Before you start installation, make sure you have logged in as root or user with sudo privileges.

Installing Mono on Debian

Standard Debian repositories does not includes Mono package. We will install the Mono package from the official Mono’s repositories. It is a very easy to install. Perform the following steps:

1. Start by installing the necessary packages:

sudo apt update

sudo apt install dirmngr gnupg apt-transport-https ca-certificates

2. Import the repository’s GPG keys using below command:

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF

The output should look like below:

gpg: key A6A19B38D3D831EF: public key "Xamarin Public Jenkins (auto-signing) <[email protected]>" imported
gpg: Total number processed: 1
gpg:               imported: 1

3. Add the Mono repository to your system sources list:

sudo sh -c 'echo "deb https://download.mono-project.com/repo/debian stable-buster main" > /etc/apt/sources.list.d/mono-official-stable.list'

4. Update the packages list and install Mono, after the apt repository is enabled:

sudo apt update

sudo apt install mono-complete

The mono-complete is a meta-package and it will install other required packages for Mono development, including the runtime, development tools, and all libraries.

5. Verify the installation printing the Mono version:

mono --version

At the time of writing this article, the latest stable version of Mono is 6.8.0 Stable (6.8.0.123).

Mono JIT compiler version 6.8.0.123 (tarball Tue Feb  4 21:20:43 UTC 2020)
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
    TLS:           __thread
    SIGSEGV:       altstack
    Notifications: epoll
    Architecture:  amd64
    Disabled:      none
    Misc:          softdebug 
    Interpreter:   yes
    LLVM:          yes(610)
    Suspend:       hybrid
    GC:            sgen (concurrent by default)

That’s it. Mono installed successfully on your Debian system, you can start developing your application.

Mono Program Example

We will create a simple Hello World program to check that everything is set up perfectly.

Open your text editor and create a file named hello.cs with the following content:

using System;

public class HelloWorld
{
    public static void Main(string[] args)
    {
        Console.WriteLine ("Hello World!");
    }
}

To build the program use the csc compiler:

csc hello.cs

It will create a executable with name hello.exe

Run the executable using the command below:

mono hello.exe

The output should show something like this:

Hello, World

Make the file executable to execute the program only by typing its name:

chmod +x hello.exe

You can now run the hello.exe file by typing:

./hello.exe

Conclusion

You have learned successfully how to install latest stable Mono on Debian from the official Mono repositories.

If you have any question or feedback, please leave a comment below.

Tags: debian, mono