command:

echo "12" | ./daffodil-core/target/start parse -s daffodil-test/src/test/resources/daffodil/section06/entities/charClassEntities.dfdl.xsd -r unknown

Here's my exception:

daffodil.exceptions.Abort: Usage error.
daffodil.exceptions.Assert$.abort(Assert.scala:52)
daffodil.exceptions.Assert$.usageErrorUnless(Assert.scala:36)
daffodil.exceptions.Assert$.usage(Assert.scala:27)
daffodil.compiler.ProcessorFactory.onPath(Compiler.scala:53)
at daffodil.exceptions.Assert$.abort(Assert.scala:52)
at daffodil.exceptions.Assert$.usageErrorUnless(Assert.scala:36)
at daffodil.exceptions.Assert$.usage(Assert.scala:27)
at daffodil.compiler.ProcessorFactory.onPath(Compiler.scala:53)
at daffodil.Main$.createProcessorFromSchemas(Main.scala:92)
at daffodil.Main$.run(Main.scala:271)
at daffodil.Main$.main(Main.scala:462)
at daffodil.Main.main(Main.scala)