Fix example for GNU/Linux emulation.

Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

ChangeLog

@@ -1,5 +1,8 @@
 2021-02-09  NIIBE Yutaka  <gniibe@fsij.org>
 
+	* example-cdc-gnu-linux/sample.c (main): Handle timeout by canceling
+	input.
+
 	* chopstx-gnu-linux.c (voluntary_context_switch): Fix for the case
 	when chx_idle suggests no context switch (tp_prev == tp_next).
 

example-cdc-gnu-linux/sample.c

@@ -179,7 +179,14 @@ main (int argc, const char *argv[])
 	      if (size < 0)
 		goto connection_loop;
 
-	      if (size == 1)
+	      if (size == 0)
+                /* Timeout */
+                {
+                  if (tty_send (tty, "\r\n", 2) < 0)
+                    return 0;
+                  break;
+                }
+	      else if (size == 1)
 		/* Do nothing but prompt again.  */
 		break;
 	      else if (size)