From a1df6a86bb85c79e7a4bae1e6770185c2ff8d2d3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Kijewski?= <rene.kijewski@fu-berlin.de>
Date: Mon, 10 Mar 2014 13:48:00 +0100
Subject: [PATCH] shell: don't ignore IO errors

---
 sys/shell/shell.c       | 3 +++
 tests/test_shell/main.c | 5 ++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/sys/shell/shell.c b/sys/shell/shell.c
index ed53c081f3..5529348b8b 100644
--- a/sys/shell/shell.c
+++ b/sys/shell/shell.c
@@ -217,6 +217,9 @@ static int readline(shell_t *shell, char *buf, size_t size)
         }
 
         c = shell->readchar();
+        if (c < 0) {
+            return 1;
+        }
         shell->put_char(c);
 
         /* We allow Unix linebreaks (\n), DOS linebreaks (\r\n), and Mac linebreaks (\r). */
diff --git a/tests/test_shell/main.c b/tests/test_shell/main.c
index 58245e70ee..171418dc26 100644
--- a/tests/test_shell/main.c
+++ b/tests/test_shell/main.c
@@ -53,7 +53,10 @@ static void print_echo(int argc, char **argv)
 static int shell_readc(void)
 {
     char c;
-    posix_read(uart0_handler_pid, &c, 1);
+    int result = posix_read(uart0_handler_pid, &c, 1);
+    if (result != 1) {
+        return -1;
+    }
     return (unsigned char) c;
 }