diff --git a/src/lib.rs b/src/lib.rs
index f58deb3..e70d089 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -7,9 +7,6 @@ mod radio;
 const COPYRIGHT: &'static str = "Copyright (C) 2018 Serge Vakulenko KK6ABQ";
 const VERSION: Option<&'static str> = option_env!("VERSION");
 
-extern {
-  fn radio_upload(cont_flag: c_int);
-}
 
 fn print_usage() {
   let version = VERSION.unwrap_or("-----");
@@ -91,13 +88,11 @@ pub extern "C" fn rust_main(_argc: c_int, _argv: *const *const c_char) -> c_int
     if matches.free.len() != 1 {
       print_usage();
     }
-    unsafe {
       let device = radio::connect();
       radio::read_image(&matches.free[0]);
       radio::print_version(device);
-      radio_upload(0);
+      radio::upload(device, 0);
       radio::disconnect();
-    }
   } else if config_flag {
     let conf_args = matches.free.len();
     if !(conf_args == 1 || conf_args == 2) {
@@ -119,16 +114,14 @@ pub extern "C" fn rust_main(_argc: c_int, _argv: *const *const c_char) -> c_int
       radio::save_image("device.img");
     } else {
       // Update device from text config file.
-      unsafe {
         let device = radio::connect();
         radio::download(device);
         radio::print_version(device);
         radio::save_image("device.img");
         radio::parse_config(&config_filename);
         radio::verify_config();
-        radio_upload(1);
+        radio::upload(device, 1);
         radio::disconnect();
-      }
     }
   } else if verify_flag {
     if matches.free.len() != 1 {
diff --git a/src/radio.rs b/src/radio.rs
index 3f74eb6..66b17cf 100644
--- a/src/radio.rs
+++ b/src/radio.rs
@@ -9,6 +9,7 @@ extern {
   fn radio_connect() -> *const RadioDeviceT;
   fn radio_disconnect();
   fn radio_download(device: *const RadioDeviceT);
+  fn radio_upload(cont_flag: c_int);
   fn radio_list_c();
   fn radio_verify_config();
   fn radio_print_version(device: *const RadioDeviceT, stdout: *const libc::FILE);
@@ -37,6 +38,12 @@ pub fn download(device: *const RadioDeviceT) {
   }
 }
 
+pub fn upload(_device: *const RadioDeviceT, cont_flag: c_int) {
+  unsafe {
+    radio_upload(cont_flag)
+  }
+}
+
 pub fn list() {