Section 14.23: get_error_details() Up Chapter 14: Extensions Section 14.25: Remote Functions  

14.24 Dynamic Form Fields

Dynamic form fields are enabled by setting the attributes as follows:
f001=tabname.fieldname, dynamic size=N ;
where N is the maximum size to be allowed.
These allow input fields to accept more data than will fit in the visible screen field size, making for more usable and flexible user interfaces.
 Section 14.23: get_error_details() Up Chapter 14: Extensions Section 14.25: Remote Functions