the string is of the form "VAR=value", i.e. it contains <em>=</em>
the variable is added to the child process&#8217;s environment.</p>
</li>
<li>
<p>If the string does not contain <em>=</em>, it names an environment
variable that will be removed from the child process&#8217;s environment.</p>
</li>
</ol>
</div>
<div class="paragraph">
<p>If the .env member is NULL, <code>start_command</code> will point it at the
.env_array <code>argv_array</code> (so you may use one or the other, but not both).
The memory i