r, group, and other permissions, and thus will combine all of these permissions. Returns nil.</pre><a href="https://janetdocs.org/os/chmod">Community Examples</a></div><hr><div class="binding"><span id="os/clock" class="binding-sym">os/clock</span> <span class="binding-type">cfunction</span> <span class="binding-type"><a href="https://github.com/janet-lang/janet/blob/4e5889e/src/core/os.c#L1494">source</a></span> <pre class="binding-text">(os/clock &amp;opt source)

Return the number of whole + fractional s