f 64&nbsp;bit integers
(<tt><b>"</b>nnn<b>LL"</b></tt> or <tt><b>"</b>nnn<b>ULL"</b></tt>) or
complex numbers (<tt><b>"</b>re&plusmn;im<b>i"</b></tt>). Otherwise
returns a string representation of the C&nbsp;type of a ctype object
(<tt><b>"ctype&lt;</b>type<b>&gt;"</b></tt>) or a cdata object
(<tt><b>"cdata&lt;</b>type<b>&gt;:&nbsp;</b>address"</tt>), unless you
override it with a <tt>__tostring</tt> metamethod (see
<a href="#ffi_metatype"><tt>ffi.metatype()</tt></a>).
</p>

<h3 id="pairs"><tt>iter, obj, st