r() on failure. If the signature buffer is too small, olm_pk_signing_last_error() will be &quot;OUTPUT_BUFFER_TOO_SMALL&quot;.</p></dd></dl><dl><dt class="spec value" id="val-sas_last_error"><a href="#val-sas_last_error" class="anchor"></a><code><span class="keyword">val</span> sas_last_error : <span><a href="../Types/SAS/index.html#type-t">Types.SAS.t</a> Ctypes_static.ptr</span> <span>&#45;&gt;</span> <span>char Ctypes_static.ptr</span></code></dt><dd><p><code>sas_last_error sas</code></p><p>A null termin