failed approach

gomspace/libutil/src/linux/stdio.c

@@ -0,0 +1,36 @@
+/* Copyright (c) 2013-2017 GomSpace A/S. All rights reserved. */
+
+#include <gs/util/stdio.h>
+#include <unistd.h>
+#include <poll.h>
+
+gs_error_t gs_stdio_putchar(int ch)
+{
+    const int res = putchar(ch);
+    if (res < 0) {
+        return GS_ERROR_IO;
+    }
+    return GS_OK;
+}
+
+gs_error_t gs_stdio_getchar_timed(int timeout_ms, int * ch)
+{
+    struct pollfd fds = {STDIN_FILENO, POLLIN, 0};
+    const int res = poll(&fds, 1, timeout_ms);
+
+    if (res == 0) {
+        return GS_ERROR_TIMEOUT;
+    }
+
+    if ((res > 0) && (fds.revents & POLLIN)) {
+        int tmp = getchar();
+        if (tmp >= 0) {
+            if (ch) {
+                *ch = tmp;
+            }
+            return GS_OK;
+        }
+    }
+
+    return GS_ERROR_IO;
+}