Fix for realpath not being available on all systems

utils/generate-ttl.sh

@@ -1,5 +1,12 @@
 #!/bin/bash
 
+# function not available on some systems
+if ! which realpath 2>/dev/null; then
+    function realpath() {
+        [[ $1 = /* ]] && echo "$1" || echo "$PWD/${1#./}"
+    }
+fi
+
 set -e
 
 if [ ! -d bin ]; then