With RDML User-Defined Built-In Functions, you are not required to enter the definitions manually. The definitions are registered automatically when you compile your RDML Built-In Function.
Built-In Function Definition (BIF Name)
Unless overridden by the definition of field BIF_NAME within the function it defaults to the Function name. It is recommended that the following naming convention be adopted when overriding within the function.
XX must be either UD for User-Defined or OV for Other Vendor.
YYYYYYYYYYYYYYY is the name that will describe, even to the non-programmer, what functions the BIF performs
While there aren't any mandatory naming conventions for RDML User-Defined Built-In functions, it is recommended that you follow these naming conventions, especially if you want it to be distributed:
XX identifies this as Built-In Function code; i.e. OV for Other Vendor or UD for User-Defined.
y is the type of object, either P for Program or D for Display file
999 is the unique identifier in the range:
-400 to -600 for User-Defined (UD) BIFs.
-600 to -999 for Other Vendor (OV) BIFs as per allocated range.