[B<-in> I<filename>]
[B<-out> I<filename>]
[B<-binary>]
+{- $OpenSSL::safe::opt_provider_synopsis -}
I<mac_name>
=head1 DESCRIPTION
=back
+{- $OpenSSL::safe::opt_provider_item -}
+
=item I<mac_name>
Specifies the name of a supported MAC algorithm which will be used.