diff --git a/tests/scripts/check-names.sh b/tests/scripts/check-names.sh
index 7e67cef..191594c 100755
--- a/tests/scripts/check-names.sh
+++ b/tests/scripts/check-names.sh
@@ -1,7 +1,23 @@
 #!/bin/sh
-
+#
+# This file is part of mbed TLS (https://tls.mbed.org)
+#
+# Copyright (c) 2015-2016, ARM Limited, All Rights Reserved
+#
+# Purpose
+#
+# This script confirms that the naming of all symbols and identifiers in mbed
+# TLS are consistent with the house style and are also self-consistent.
+#
 set -eu
 
+if grep --version|head -n1|grep GNU >/dev/null; then :; else
+    echo "This script requires GNU grep."
+    exit 1
+fi
+
+printf "Analysing source code...\n"
+
 tests/scripts/list-macros.sh
 tests/scripts/list-enum-consts.pl
 tests/scripts/list-identifiers.sh
@@ -9,7 +25,7 @@
 
 FAIL=0
 
-printf "Exported symbols declared in header: "
+printf "\nExported symbols declared in header: "
 UNDECLARED=$( diff exported-symbols identifiers | sed -n -e 's/^< //p' )
 if [ "x$UNDECLARED" = "x" ]; then
     echo "PASS"
@@ -24,7 +40,7 @@
 for THING in actual-macros enum-consts; do
     printf "Names of $THING: "
     test -r $THING
-    BAD=$( grep -v '^MBEDTLS_[0-9A-Z_]*[0-9A-Z]$' $THING || true )
+    BAD=$( grep -v '^MBEDTLS_[0-9A-Z_]*[0-9A-Z]$\|^YOTTA_[0-9A-Z_]*[0-9A-Z]$' $THING || true )
     if [ "x$BAD" = "x" ]; then
         echo "PASS"
     else
@@ -66,6 +82,7 @@
     FAIL=1
 fi
 
+printf "\nOverall: "
 if [ "$FAIL" -eq 0 ]; then
     rm macros actual-macros enum-consts identifiers exported-symbols
     echo "PASSED"