The way that I've avoided obsolesence is to not use binary storage at
all. All of my test and measurement results get stored in a SQL Server
database (actually, they're first written as XML and imported).
Oracle, MySQL will work just as well and even Access in a pinch. I
have had the same issue you face and long term support has always been
a problem. With the standard database approach, users will often
already have the tools necessary to view and analyze the data(i.e. MS
Query) and that relieves you of providing a program that does that.
Adding or removing columns, modifying the entire schema, is relatively
simple and importing old data to a new database format is something
I've done a couple of times recently with lttle impact. If the time it
takes to write to a database is a concern, then maybe you could move
the datalog files as a post-processing step.
