use tcpserver shutdown

src/main.c

@@ -50,8 +50,7 @@ static void signal_handler(int signal) {
 		wavfile_close(file);
 	}
 	free(filepath);
-	shutdown(sock, SHUT_RDWR);
-	close(sock);
+	tcpserver_stop(sock);
 	exit(EXIT_SUCCESS);
 }
 

src/tcpserver.c

@@ -49,5 +49,6 @@ int tcpserver_start(const char *address, uint16_t port) {
  *
  */
 void tcpserver_stop(int sock) {
+	shutdown(sock, SHUT_RDWR);
 	close(sock);
 }