### Running rustup-init for initial setup

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/other.md

Command to run rustup-init when the package manager only provides this command, for initial setup.

```shell
rustup-init
```

--------------------------------

### Development build command

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/index.md

Example of building and installing rustup into a temporary directory for development.

```bash
cargo build
mkdir home
RUSTUP_HOME=home CARGO_HOME=home target/debug/rustup-init --no-modify-path -y
```

--------------------------------

### Download previous version of rustup-init

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/other.md

This example shows how to download a specific previous version of rustup-init for a given target tuple.

```bash
https://static.rust-lang.org/rustup/archive/{rustup-version}/{target-tuple}/rustup-init[.exe]
```

--------------------------------

### Passing arguments to rustup-init via shell script

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/other.md

Examples of passing arguments to the rustup-init script through the shell.

```shell
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --help
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --no-modify-path
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --default-toolchain nightly
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --default-toolchain none
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --profile minimal --default-toolchain nightly
```

--------------------------------

### Installing a specific host toolchain

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/concepts/toolchains.md

Example of installing a toolchain with a specific host target tuple, such as a 32-bit compiler or the MSVC toolchain on Windows.

```bash
$ rustup toolchain install stable-x86_64-pc-windows-msvc
```

--------------------------------

### Running rustup-init with tracing enabled

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Example command to run a rustup operation (e.g., 'show') with tracing enabled, using the built rustup-init binary.

```sh
RUSTUP_FORCE_ARG0="rustup" ./target/debug/rustup-init show

```

--------------------------------

### Correct .profile configuration for Mac with Homebrew and rustup

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/already-installed-rust.md

Example of how to configure the .profile file to ensure rustup proxies take precedence.

```bash
eval $(/opt/homebrew/bin/brew shellenv)
. $HOME/.cargo/env
```

--------------------------------

### Basic Instrumentation

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Example of how to instrument a function with tracing.

```rust
#[tracing::instrument(level = "trace", err(level = "trace"), skip_all)]
```

--------------------------------

### Successful cargo version output (stable toolchain installed)

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/already-installed-rust.md

Example output of 'cargo +stable --version' when the stable toolchain is installed.

```text
cargo 1.85.1 (d73d2caf9 2024-12-31)
```

--------------------------------

### Example of incorrect command output

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/already-installed-rust.md

Illustrates the error message seen when cargo is not a rustup proxy.

```text
error: no such command: `+stable`

        Cargo does not handle `+toolchain` directives.
        Did you mean to invoke `cargo` through `rustup` instead?
```

--------------------------------

### Enable tab completion for Fish

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/index.md

Generates and installs the completion script for Fish.

```shell
# Fish
$ mkdir -p ~/.config/fish/completions
$ rustup completions fish > ~/.config/fish/completions/rustup.fish
```

--------------------------------

### Enable tab completion for Bash

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/index.md

Generates and installs the completion script for Bash.

```shell
# Bash
$ rustup completions bash > ~/.local/share/bash-completion/completions/rustup
```

--------------------------------

### Install nightly toolchain with specific components

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/index.md

Installs the nightly toolchain, allowing downgrades to find necessary components, and includes 'clippy'.

```shell
rustup toolchain install nightly --allow-downgrade --profile minimal --component clippy
```

--------------------------------

### Enable tab completion for PowerShell v5.0+

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/index.md

Generates and installs the completion script for PowerShell.

```powershell
# PowerShell v5.0+
$ rustup completions powershell >> $PROFILE.CurrentUserCurrentHost
# or
$ rustup completions powershell | Out-String | Invoke-Expression
```

--------------------------------

### Enable tab completion for Zsh

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/index.md

Generates and installs the completion script for Zsh.

```shell
# Zsh
$ rustup completions zsh > ~/.zfunc/_rustup
```

--------------------------------

### Verify Rust installation

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/index.md

After installation, you can verify that Rust is installed correctly by checking the rustc version.

```console
rustc --version
```

--------------------------------

### Install GNU toolchain

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/windows.md

Install the GNU toolchain for use, even if not set as the default.

```bash
$ rustup toolchain install stable-gnu
```

--------------------------------

### APT installation of rustup

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/other.md

Command to install rustup using the APT package manager on Debian or Ubuntu.

```shell
sudo apt install rustup
```

--------------------------------

### Install with specific profile

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/concepts/profiles.md

Command to directly select the profile used when installing a toolchain.

```console
rustup install --profile <name>
```

--------------------------------

### Successful cargo version output (stable toolchain not installed)

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/already-installed-rust.md

Example output of 'cargo +stable --version' when the stable toolchain is not installed.

```text
error: toolchain 'stable' is not installed
```

--------------------------------

### Common rustup commands

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/examples.md

A table of common rustup commands and their descriptions.

```bash
rustup default nightly
```

```bash
rustup set profile minimal
```

```bash
rustup target list
```

```bash
rustup target add arm-linux-androideabi
```

```bash
rustup target remove arm-linux-androideabi
```

```bash
rustup run nightly rustc foo.rs
```

```bash
rustc +nightly foo.rs
```

```bash
rustup run nightly bash
```

```bash
rustup default stable-msvc
```

```bash
rustup override set nightly-2015-04-01
```

```bash
rustup toolchain link my-toolchain "C:\RustInstallation"
```

```bash
rustup show
```

```bash
rustup toolchain uninstall nightly
```

```bash
rustup toolchain help
```

```bash
rustup man cargo
```

--------------------------------

### Add Android target

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/cross-compilation.md

Example of adding the Android target to rustup, showing the download and install process.

```console
$ rustup target add arm-linux-androideabi
info: downloading component 'rust-std' for 'arm-linux-androideabi'
info: installing component 'rust-std' for 'arm-linux-androideabi'
```

--------------------------------

### Build and open the book

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/README.md

Builds the book and opens it in a web browser.

```console
mdbook build --open
```

--------------------------------

### Conditional Instrumentation with otel feature

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Example of instrumenting a function only when the 'otel' feature is enabled using cfg_attr.

```rust
#[cfg_attr(feature="otel", tracing::instrument(level = "trace", err(level = "trace"), skip_all))]
```

--------------------------------

### Serve the book

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/README.md

Launches a local web server for the book with automatic rebuilding and browser reloading.

```console
mdbook serve
```

--------------------------------

### Running Jaeger Docker container

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Command to start a Jaeger all-in-one Docker container for OpenTelemetry tracing.

```sh
docker run -d --name jaeger   -e COLLECTOR_ZIPKIN_HOST_PORT=:9411   -e COLLECTOR_OTLP_ENABLED=true   -p 6831:6831/udp   -p 6832:6832/udp   -p 5778:5778   -p 16686:16686   -p 4317:4317   -p 4318:4318   -p 14250:14250   -p 14268:14268   -p 14269:14269   -p 9411:9411   jaegertracing/all-in-one:latest

```

--------------------------------

### Legacy stderr output format

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Example of rustup's log output when RUSTUP_LOG is not set, mimicking older versions.

```console
> rustup default stable
info: using existing install for 'stable-aarch64-apple-darwin'
info: default toolchain set to 'stable-aarch64-apple-darwin'

  stable-aarch64-apple-darwin unchanged - rustc 1.79.0 (129f3b996 2024-06-10)

```

--------------------------------

### Install rustup from source

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/installation/other.md

This command checks out the rustup git repository and builds it from source using cargo.

```bash
git clone https://github.com/rust-lang/rustup
cd rustup
cargo run --release
```

--------------------------------

### rustup dump-testament output

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/version-numbers.md

Example output from the `rustup dump-testament` hidden command, showing detailed version information.

```shell
$ rustup dump-testament
Rustup version renders as: 1.18.3+15 (a54051502 2019-05-26) dirty 1 modification
Current crate version: 1.18.3
Built from branch: kinnison/version-strings
Commit info: 1.18.3+15 (a54051502 2019-05-26)
Modified: CONTRIBUTING.md

```

--------------------------------

### Tracing dependencies with RUSTUP_LOG=trace

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Example showing log lines from rustup's dependencies (e.g., hyper_util) when RUSTUP_LOG is set to 'trace'.

```console
> RUSTUP_LOG=trace rustup update
[..]
2024-06-16T12:12:45.569428Z TRACE hyper_util::client::legacy::client: http1 handshake complete, spawning background dispatcher task
2024-06-16T12:12:45.648682Z TRACE hyper_util::client::legacy::pool: pool dropped, dropping pooled (("https", static.rust-lang.org))

   stable-aarch64-apple-darwin unchanged - rustc 1.79.0 (129f3b996 2024-06-10)
  nightly-aarch64-apple-darwin unchanged - rustc 1.81.0-nightly (3cf924b93 2024-06-15)

2024-06-16T12:12:45.693350Z  INFO rustup::cli::rustup_mode: cleaning up downloads & tmp directories

```

--------------------------------

### Using RUSTUP_FORCE_ARG0

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tips-and-tricks.md

Example of how to use the RUSTUP_FORCE_ARG0 environment variable to simulate a specific binary when running with cargo run.

```console
> cargo run --config env.RUSTUP_FORCE_ARG0=\'rustup\' -- show
```

--------------------------------

### Example of linking and setting a custom toolchain

Source: https://github.com/rust-lang/rustup/blob/main/doc/user-guide/src/concepts/toolchains.md

Demonstrates linking a custom toolchain built from the rust-lang/rust repository and setting it as the default.

```bash
$ rustup toolchain link my-toolchain ~/rust/build/x86_64-unknown-linux-gnu/stage2/
$ rustup default my-toolchain
```

--------------------------------

### Custom logging mode with RUSTUP_LOG

Source: https://github.com/rust-lang/rustup/blob/main/doc/dev-guide/src/tracing.md

Example of rustup's log output when RUSTUP_LOG is set, using tracing_subscriber's builtin format.

```console
> RUSTUP_LOG=trace rustup default stable
2024-06-16T12:08:48.732894Z  INFO rustup::cli::common: using existing install for 'stable-aarch64-apple-darwin'
2024-06-16T12:08:48.739232Z  INFO rustup::cli::common: default toolchain set to 'stable-aarch64-apple-darwin'

  stable-aarch64-apple-darwin unchanged - rustc 1.79.0 (129f3b996 2024-06-10)

```