sh">DESCRIPTION</h2>
<p class="level0">Data <span Class="emphasis">pointer</span> to pass to the file read function. If you use the <a Class="emphasis" href="./CURLOPT_READFUNCTION.html">CURLOPT_READFUNCTION</a> option, this is the pointer you'll get as input in the 4th argument to the callback. 
<p class="level0">If you don't specify a read callback but instead rely on the default internal read function, this data must be a valid readable FILE * (cast to 'void *'). 
<p class="level0">If you're using libcur