From Nothing To Hello World

This page describes the quickest way to test a program on Redox. This tutorial doesn't build Redox from source.

In this example we will use a "Hello World" program written in Rust.

Download the script to bootstrap Podman and download the Redox build system.

curl -sf https://gitlab.redox-os.org/redox-os/redox/raw/master/podman_bootstrap.sh -o podman_bootstrap.sh

Execute the downloaded script.
```
time bash -e podman_bootstrap.sh
```
Enable the Rust toolchain in the current shell.
```
source ~/.cargo/env
```
Navigate to the Redox build system directory.
```
cd ~/tryredox/redox
```
Create the .config file and add the REPO_BINARY environment variable to enable the binary-mode.
```
echo "REPO_BINARY?=1 \n CONFIG_NAME?=my_config" >> .config
```

Create the hello-world recipe folder.

mkdir cookbook/recipes/other/hello-world

Create the source folder for the recipe.

mkdir cookbook/recipes/other/hello-world/source

Navigate to the recipe's source folder.

cd cookbook/recipes/other/hello-world/source

Initialize a Cargo project with the "Hello World" string.
```
cargo init --name="hello-world"
```

Create the hello-world recipe configuration.

cd ~/tryredox/redox

nano cookbook/recipes/other/hello-world/recipe.toml

Add the following to the recipe configuration:
```
[build]
template = "cargo"
```

Create the my_config filesystem configuration.

cp config/x86_64/desktop.toml config/x86_64/my_config.toml

Open the my_config filesystem configuration file (i.e., config/x86_64/my_config.toml) and add the hello-world package to it.
```
[packages]
# Add the item below
hello-world = "source"
```
Build the Hello World program and the Redox image.
```
time make prefix r.hello-world image
```
Start the Redox virtual machine without a GUI.
```
make qemu gpu=no
```
At the Redox login screen, write "user" for the user name and press Enter.
Run the "Hello World" program.
```
helloworld
```
Shut down the Redox virtual machine.
```
sudo shutdown
```

The Redox Operating System