ts(1): digest option is mandatory
not specifying the digest both on command line and in the config file
will lead to response generation aborting with
140617514493760:error:2F098088:time stamp routines:ts_CONF_lookup_fail: \
cannot find config variable:crypto/ts/ts_conf.c:106:tsr_test::signer_digest
@@ -262,7 +262,7 @@ specified, the argument is given to the engine as a key identifier.
=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
@@ -460,7 +460,8 @@ command line option. (Optional)
=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>
