=item B<-I<digest>>
Signing digest to use. Overrides the B<signer_digest> config file
-option. (Optional)
+option. (Mandatory unless specified in the config file)
=item B<-chain> certs_file.pem
=item B<signer_digest>
Signing digest to use. The same as the
-B<-I<digest>> command line option. (Optional)
+B<-I<digest>> command line option. (Mandatory unless specified on the command
+line)
=item B<default_policy>