Specifies a string expression that must evaluate to a single operating system command. If you specify systemcommand, the statement executes the command and returns automatically to the application, either immediately after starting the command (if CurSession.ProcessWait=FALSE) or after the command has finished (if CurSession.ProcessWait=TRUE). In the latter case the application can inquire the status of the executed command by using the CurSession.CallSystemStatus attribute. If you do not specify a system command, the statement puts the user at the operating system prompt (if CurSession.ProcessWindow=TRUE). The user can then execute any operating system commands and return to the application by entering the exit command.