When reading in user defined type records from a binary file, is there a way to read in to a variable which record it is accessing?

I've opened a file for binary read, and have the following:

Code:
dim x as integer
dim ReadData as udtType

Do Until EOF(gdvFileNumber)
     get FileNum, , ReadData
Loop
I would like to be able to add the record number it is currently accessing to a list box.

In the case of binary files, are records just in numerical order (ie: record 1, 2, 3, 4...), or do they depend on the length of each record (1, 13, 20...)?

Thank you.