Function hyper_headers_foreach 

#[unsafe(no_mangle)]
pub extern "C" fn hyper_headers_foreach(
    headers: *const hyper_headers,
    func: extern "C" fn(*mut c_void, *const u8, usize, *const u8, usize) -> c_int,
    userdata: *mut c_void,
)

Available on crate feature ffi and hyper_unstable_ffi only.

Iterates the headers passing each name and value pair to the callback.

The userdata pointer is also passed to the callback.

The callback should return HYPER_ITER_CONTINUE to keep iterating, or HYPER_ITER_BREAK to stop.