recover the terminal's behaviour when runing exit in finsh

bsp/simlinux/drivers/board.c

@@ -67,6 +67,18 @@ _CRTIMP void __cdecl abort(void);
 void rt_hw_exit(void)
 {
     rt_kprintf("RT-Thread, bye\n");
+#if !defined(_WIN32) && defined(__GNUC__)
+    /* *
+     * getchar reads key from buffer, while finsh need an non-buffer getchar
+     * in windows, getch is such an function, in linux, we had to change 
+     * the behaviour of terminal to get an non-buffer getchar. 
+     * in usart_sim.c, set_stty is called to do this work 
+     * */
+    {
+        extern void restore_stty(void);
+        restore_stty();
+    }
+#endif
     exit(0);
 }
 FINSH_FUNCTION_EXPORT_ALIAS(rt_hw_exit, exit, exit rt - thread);

bsp/simlinux/drivers/usart_sim.c

@@ -129,19 +129,25 @@ static int savekey(unsigned char key)
 static DWORD WINAPI ThreadforKeyGet(LPVOID lpParam)
 #else
 
+static struct termios oldt, newt;
 /*simulate windows' getch(), it works!!*/
-static void setgetchar(void) 
+void set_stty(void) 
 {
-    struct termios oldt, newt;
-
-	// get terminal input's attribute
+	/* get terminal input's attribute */
     tcgetattr(STDIN_FILENO, &oldt);
     newt = oldt;
 
-	//set termios' local mode
+	/* set termios' local mode */
     newt.c_lflag &= ~(ECHO|ICANON);
     tcsetattr(STDIN_FILENO, TCSANOW, &newt);
 }
+
+void restore_stty(void)
+{
+   /* recover terminal's attribute */
+   tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
+}
+
 #define getch  getchar
 
 static void * ThreadforKeyGet(void * lpParam)
@@ -154,7 +160,7 @@ static void * ThreadforKeyGet(void * lpParam)
 	/* set the getchar without buffer */
 	sigfillset(&sigmask);
 	pthread_sigmask(SIG_BLOCK, &sigmask, &oldmask);
- 	setgetchar();
+	set_stty();
 #endif
     (void)lpParam;              //prevent compiler warnings
     for (;;)