What can I do with an unloaded partitioned data set on Linux?

[Hendrik Boom <hendrik@topoi.pooq.com>]

I am the proud owner of several unloaded partitioned data sets, dating 
back to my days on OS/360 and OS/370.

Does anyone have any code I could use to decode these?  I don't mean the 
EBCDIC-to-ASCII (or to UTF-8) conversion -- I mean the weird file format.

Or documentation about this file format?

Or will I have to reverse-engineer it myself?  Not that that's likely to 
be an insurmountable task.  I just suspect that somewhere, someone has 
already done it.

-- hendrik