| ### Overview - Using the DCE Control Program Command Language Preview Variable Substitution Provides a Convenient Shorthand Command Substitution Offers Flexibility and Convenience Grouping Elements and Controlling Interpretation Documenting Scripts with Comments Convenience Variables Measuring and Counting with Expressions Operating on Lists Controlling Scripts Creating Commands Dynamically Reading Other Files as dcecp Scripts Creating New Commands String Manipulation Dealing with Errors and Exceptions Working With Files Spawning Subprocesses ###