Index: uspace/lib/posix/unistd.c
===================================================================
--- uspace/lib/posix/unistd.c	(revision f1fae414fd9fd1d6dafa676d0cd3e128d33393dd)
+++ uspace/lib/posix/unistd.c	(revision 8d7e82c1c02f3c7b1ece4573180e967341db9006)
@@ -43,12 +43,13 @@
 
 /**
- * 
+ * Dummy function. Always returns false, because there is no easy way to find
+ * out under HelenOS.
+ *
  * @param fd
- * @return
+ * @return Always false.
  */
 int posix_isatty(int fd)
 {
-	// TODO
-	not_implemented();
+	return false;
 }