Couple of points of clarifications...
the IFS is a record-based file, a save file, or a stream file?
Keeping in mind that symbolic links could be used to make a
file in /QOpnSys/ (for example) point to a file in /QSYS.LIB
When you say record based... are you talking about an as/400 pf? or any database file (ie: oracle, access)
save file... Maybe a pattern search, in the object for identification... i'll give it a try... plus also I have seen that save files are a certain record length, so it could be divisible by that number and check for no remainder.
not sure how the sym links work... not even sure if I have any...
-tim