maybe I should comment on this one as I am the one who had problems.
I write out rootfiles from within our (BaBar) reco software. By
default, the BaBar link to Root (still) points to 2.21/08 and this got
sucked into the executable. I had produced a so-lib with my class and
dictionary based on 2.22/09. When I ran my program, I did not get any
error message, but an empty outputfile. The tree was (as far as I can
tell) fine, it was just empty.
This is probably due to 2.21/08 not being forward compatible (but
then, I don't know of any software that is forward compatible -- apart
from trivial cases, that is ...)
When doing everything consistently in 2.22/09 (and 2.21/08, I presume,
but I have not tested it) it works fine.
Cheers,
--U.
> Hi Matt,
> Could you clarify your 2nd point about "Incompatible changes in the
> I/O subsystem". Version 2.22 IS BACKWARD COMPATIBLE with 2.21.
> Files written by 2.21 are readable by 2.22 and no changes at all
> are required in the code. Only the files written by 2.22 cannot be read
> by 2.21. The reasons for this are explained in the release notes.
> I would appreciate if you could tell us asap what is the problem
> as we are getting mails from users worried by your message.