### Install krb5 for GSS API on Windows

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Command to install krb5 on Windows using vcpkg, required for GSS API authorization.

```shell
vcpkg install krb5
```

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

### Install libsodium for CURVE on Windows

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Command to install libsodium on Windows using vcpkg, required for CURVE authorization.

```shell
vcpkg install --triplet "x64-windows-md" libsodium
```

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

### Rust ZeroMQ Request-Reply Example

Source: https://github.com/mgaertne/arzmq/blob/master/README.md

Demonstrates setting up a ZeroMQ context, binding a reply socket, and connecting a request socket to send a message. It utilizes the arzmq crate for asynchronous ZeroMQ operations.

```rust
use std::thread;

use arzmq::prelude::{Context, RequestSocket, ReplySocket, SendFlags, Receiver, RecvFlags, Sender};

fn run_reply(context: &Context, endpoint: &str) {
    let socket = ReplySocket::from_context(context).unwrap();
    socket.bind(endpoint).unwrap();
    
    thread::spawn(move || {
       while socket.recv_msg(RecvFlags::DONT_WAIT).is_err() {}
    });
}

fn main() {
    let ctx = Context::new().unwrap();
    
    run_reply(&ctx, "tcp://127.0.0.1:1234");

    let socket = RequestSocket::from_context(&ctx).unwrap();
    socket.connect("tcp://127.0.0.1:1234").unwrap();
    let _ = socket.send_msg("hello world!", SendFlags::DONT_WAIT);
}
```

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

### Install libsodium for CURVE on MacOS

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Command to install libsodium on MacOS using Homebrew, necessary for CURVE authorization.

```shell
brew install libsodium
```

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

### Install libgssapi-krb5 for GSS API on Linux

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Command to install the libgssapi-krb5 package on Linux systems using apt-get, required for GSS API authorization.

```bash
sudo apt-get install libgssapi-krb5
```

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

### Install libsodium for CURVE on Linux

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Command to install the libsodium development package on Linux systems using apt-get, required for CURVE authorization.

```bash
sudo apt-get install libgsodium-dev
```

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

### Configure GSSAPI for MacOS

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Environment variables to set on MacOS to utilize the built-in Kerberos framework for GSSAPI authorization.

```shell
export SYSTEM_DEPS_GSSAPI_LIB_FRAMEWORK=Kerberos
export SYSTEM_DEPS_GSSAPI_NO_PKG_CONFIG=1
```

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

### Conditional Compilation with zmq_has cfg - Rust

Source: https://github.com/mgaertne/arzmq/blob/master/features.md

Demonstrates how to conditionally compile Rust code based on whether a specific libzmq feature (like 'curve') is enabled and working. This uses the `zmq_has` attribute provided by the crate's build script.

```rust
#[cfg(zmq_has = "curve")]
fn only_working_when_curve_is_enabled_and_working() { ... }
```

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