Can we use variable in Redwood for System id's.

Hi All:

              We have 3 major system id's that we use Redwood in (pr1, dvb, and qa1)

              In our File_Event_Definitions we use a string for the directory of the following nature :

                                       /aafcdata/bcss/pr1/glpost_i_agririsk/in   ....

              We would like to replace the "pr1" system id here with a variable that would change based on which current system we are looking at.

              Does anyone know how to do this ? Need to know how to create the variable's , how to use them in this environment.

  Thanks ,

Patrick Donnelly