What is the maximum size of a report?

A customer was running a "large" report to the screen, and got a C-Assert:

Module: RT.C.4903

Process: 0LA/Input - PRINT ON SCREEN

Bad Prt Write - Error - Already on File

When using a Form defined with a length of zero, the maximum size of a text report displayed on the screen is 65,535 lines. If the Form Length is not zero or the Form Type is PDF there is no limit.