I am writing an application that uses command-line (from scheme/cmdline) to parse command line arguments. Consider the following simple test-app.ss program: #lang scheme (define verbose-mode (make-parameter #f)) (define input-file (make-parameter "input.xml")) (define output-directory (make-parameter "output")) (command-line #:program "test-app" #:once-each [("-v" "--verbose") "Generate with verbose messages" (verbose-mode #t)] [("-i" "--input-file") if "Input file" (input-file if)] [("-o" "--output-directory") od "Output directory" (output-directory od)] #:args () (void)) (printf "Test Command-Line Application~n") (printf " verbose-mode = ~a~n" (verbose-mode)) (printf " input-file = ~s~n" (input-file)) (printf " output-directory = ~s~n" (output-directory)) When I make an executable of this using Scheme>Create Executable ... and select Stand-alone and MzScheme, I can get it to work, but I have some questions. Why do I need "--" before my arguments? [They seem to be parsed by MzScheme if I don't.] For example: >test-app -v Welcome to MzScheme v4.2 [3m], Copyright (c) 2004-2009 PLT Scheme Inc. Test Command-Line Application verbose-mode = #f input-file = "input.xml" output-directory = "output" I get the MzScheme banner and my application doesn't see the "-v". So presumable, MzScheme parsed it. >test-app -- -v Test Command-Line Application verbose-mode = #t input-file = "input.xml" output-directory = "output" Works as expected. Is there any way to get this behavior without the "--"? Should I be using mzc to compile it instead of DrScheme? It seems to work as expected if I select Launcher when using Scheme>Create Executable .... What is the best way to test programs using command-line during development? It seems I'd like to be able to tell if I am NOT being executed from the command line and do some alternate processing in that case - either use the defaults or use current-command-line-arguments to set specific values and let command-line parse those. Any help/thoughts would be welcome. Thanks, Doug