+/** \brief \c NULL resistant strncasecmp.
+ * \param[in] a the first string.
+ * \param[in] b the second string.
+ * \param[in] n the number of maximum chars to compare.
+ * \return <tt>strncasecmp(a, b)</tt>, and treats \c NULL strings like \c ""
+ * ones, as if we were in the C locale.
+ */
+int ascii_strncasecmp(const char *a, const char *b, ssize_t n)