std::mktime and timezone info
<p>I'm trying to convert a time info I reveive as a UTC string to a timestamp using <code>std::mktime</code> in C++. My problem is that in <code>&lt;ctime&gt;</code> / <code>&lt;time.h&gt;</code> there is no function to convert to UTC; mktime will only return the timestamp as local time.</p>

<p>So I need to figure out the timezone offset and take it into account, but I can't find a platform-independent way that doesn't involve porting the whole code to <code>boost::date_time</code>. Is there some easy solution which I have overlooked?</p>
