printing multiple files

[Bill Wyatt]

I'm writing my own backend program. Among other things, the ability to
have multiple files in one call to 'lp' is useful.

It appears that all the files going into a print file, while given
different control files (lp-00001-001, lp-00001-002, etc.) are
identified only by the first file in the list. Is this true? I can't
put a different header on each sucessive file's listing, for example?
Have I configured something wrong or overlooked some field?

Thanks,
Bill