# Host files

File path: `out/dir/api.rs`

```rust
// Host code
/* Rust API */
#[derive(Debug)]
pub enum Commands {
    /// Call out an outstanding person
    #[allow(non_camel_case_types)]
    call_me_back_outstanding {
        callback: extern "C" fn(trixy::types::String) -> trixy::types::String,
    },
    One(one::One),
}
pub mod one {
    #[derive(Debug)]
    pub enum One {
        /// Call out a person
        #[allow(non_camel_case_types)]
        call_me_back { callback: extern "C" fn(trixy::types::u32) },
    }
}
/* C API */
#[no_mangle]
pub extern "C" fn call_me_back_outstanding(
    callback: extern "C" fn(trixy::types::String) -> trixy::types::String,
) -> core::ffi::c_int {
    callback_function(crate::Commands::call_me_back_outstanding {
        callback: match callback.try_into() {
            Ok(ok) => ok,
            Err(err) => {
                trixy::types::traits::errno::set(err.into());
                return 0;
            }
        },
    });
    return 1;
}
pub mod one_c {
    #[allow(unused_imports)]
    use crate::callback_function;
}
#[no_mangle]
pub extern "C" fn one_call_me_back(
    callback: extern "C" fn(trixy::types::u32),
) -> core::ffi::c_int {
    callback_function(
        crate::Commands::One(crate::one::One::call_me_back {
            callback: match callback.try_into() {
                Ok(ok) => ok,
                Err(err) => {
                    trixy::types::traits::errno::set(err.into());
                    return 0;
                }
            },
        }),
    );
    return 1;
}
// vim: filetype=rust
```

# Auxiliary files

File path: `dist/interface.h`

```c
#if !defined TRIXY_MAIN_HEADER
#define TRIXY_MAIN_HEADER

#include "errno.h"
#include "string.h"
#include "vec.h"

/**
 * Call out an outstanding person
 */
extern int call_me_back_outstanding (const char *(*callback) (const char *));

/**
 * Call out a person
 */
extern int one_call_me_back (void (*callback) (uint32_t));

struct one
{
  int (*call_me_back) (void (*callback) (uint32_t));
};

const struct one one = {
  .call_me_back = one_call_me_back,
};

#endif // if !defined TRIXY_MAIN_HEADER
// vim: filetype=c
```