I don't really understand what it is you are trying to do, but the Options >> Tools Menu Options >> Command Line field allows you to associate a user defined Tools menu option with a command line statement that you want to execute when it is selected. You only need to create the entire command line statement with arguments for the external process to have it passed to it. In order for the external process to take the type of information you are describing it has to be built to accept that type of data at the command line, there is nothing special CVI can do to make it perform differently than it was intended.
For more information on this option you can look in the LabWindows/CVI User's Manual or if you have CVI 6.0 just click the context sensitive Help button
at the bottom of the Tools Menu Options dialog.
Jason F.
Applications Engineer
National Instruments
www.ni.com/ask