The Object Server Communications Area (OSCA) user class is used to communicate between an OpenROAD client and an OpenROAD Server application. An instance of this class must be passed using BYREF whenever a GSCP is called. This passes a context token from client to server and errors from server to client. A system variable of this class called OSCA is available.

For more information about OSCA in an OpenROAD client application, see uc_osca (OpenROAD Client) (see uc_osca (OpenROAD Client)).