Type Definition windows_sys::Win32::Networking::WindowsWebServices::WS_OPEN_CHANNEL_CALLBACK

pub type WS_OPEN_CHANNEL_CALLBACK = Option<unsafe extern "system" fn(channelinstance: *const c_void, endpointaddress: *const WS_ENDPOINT_ADDRESS, asynccontext: *const WS_ASYNC_CONTEXT, error: *const WS_ERROR) -> HRESULT>;

Required features: "Win32_Networking_WindowsWebServices"