Function grpcio_sys::grpcwrap_call_start_duplex_streaming

pub unsafe extern "C" fn grpcwrap_call_start_duplex_streaming(
    call: *mut grpc_call, 
    ctx: *mut grpcwrap_batch_context, 
    initial_metadata: *mut grpc_metadata_array, 
    initial_metadata_flags: u32, 
    tag: *mut c_void
) -> grpc_call_error