Update core/utils.h

Co-authored-by: Reto Schneider <[email protected]>

core/utils.h

@@ -59,7 +59,7 @@ lwm2m_client_t *utils_findClient(lwm2m_context_t *contextP, void *fromSessionH);
 #endif
 /** A safer version of `strlen`. Finds the number of chars (bytes) of the given string up to a given max. length.
  *
- * The behaviour is undefined if the provided maximum length is bigger than the reserved memory for the given string.
+ * The behaviour is undefined if the maximum length value is bigger than the actually reserved memory behind the @a str buffer.
  *
  * @param str The null-terminated string to find the length of.
  * @param max_size Max size of string.