d">long</span>, a <span Class="bold">function pointer</span>, an <span class="bold">object pointer</span> or a <span Class="bold">curl_off_t</span> type, depending on what the specific option expects. Read this manual carefully as bad input values may cause libcurl to behave badly!  You can only set one option in each function call. 
<p class="level0"><a name="OPTIONS"></a><h2 class="nroffsh">OPTIONS</h2>
<p class="level0">
<p class="level0"><a name="CURLMOPTSOCKETFUNCTION"></a><span class="nroffip">CURLMOP