title: what's the difference between int and cl_int in OpenCL?
body: <p>There are many data types in OpenCL, such as <code>int</code>, <code>cl_int</code>, <code>char</code>, <code>cl_char</code>, 'short', 'cl_short'. But what is the difference between <code>int</code> and <code>cl_int</code>, and when should I use <code>cl_int</code> instead of <code>int</code>?</p>