Function gpgme_sys::gpgme_op_export_keys_start

pub unsafe extern "C" fn gpgme_op_export_keys_start(
    ctx: gpgme_ctx_t, 
    keys: *mut gpgme_key_t, 
    mode: gpgme_export_mode_t, 
    keydata: gpgme_data_t
) -> gpgme_error_t