either True or False </li>
<li><a href="libqhull.h#CENTERtype">CENTERtype</a> to
distinguish facet-&gt;center </li>
<li><a href="libqhull.h#qh_PRINT">qh_PRINT</a> output
formats for printing (qh.PRINTout) </li>
<li><a href="libqhull.h#qh_ALL">qh_ALL</a> argument flag
for selecting everything </li>
<li><a href="libqhull.h#qh_ERR">qh_ERR</a> Qhull exit status codes
for indicating errors </li>
<li><a href="libqhull.h#qh_FILEstderr">qh_FILEstderr</a> Fake stderr
to distinguish error output from normal output [C