e_getenv&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;string<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;putenv&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;unit<br>
&nbsp;&nbsp;<span class="keyword">type</span>&nbsp;process_status&nbsp;=<br>
&nbsp;&nbsp;&nbsp;&nbsp;<span class="constructor">Unix</span>.process_status&nbsp;=<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="constructor">WEXITED