The Commarea is an area of your program generated by Online Express that stores data you pass between programs.
Online Express automatically creates a Commarea; you simply specify the size of the largest record that your program can send or receive in the Extra Commarea Bytes field on the Express Generation Options window. To access this window, from the File menu, select Express Generation Options.
When you generate your program, the following code is generated to create a storage area in Commarea.
Online Express calculates the number of savekeybytes as the key length of each window record that can be updated, plus a one-byte flag per key. For scrollable SQL records, Online Express calculates savekeybytes as the length of each Order By column, plus a one-byte flag per key.
Alternatively, you can define a Commarea data structure object in your application's Globals folder using the Data Structure Editor. See CA, CA05, and CADS for more information.