Question about TFile

From: Reid D Rivenburgh (reid@lanl.gov)
Date: Wed Oct 29 1997 - 22:26:43 MET 

Hi,

I have a question about TFile.  In our application we're developing a
class that will act as a sort of database, having a convenient
interface for persistently storing and retrieving ROOT objects.  One
of its members will be a TFile, which will do most of the work of
storing and retrieving.  My question, then, is how will this class
(and possibly multiple instances of it) having a TFile interere with
other TFiles created by the main program?  In most ROOT examples I've
seen and in code I've written, there's only ever one TFile in
existence at a time.  The TROOT class seems to maintain a "current
TFile" for when an object calls its Write() method.  When I create one
of these database objects, though, I probably don't want its TFile to
become the current one.  And, I don't want the database object to
write every object in memory to its TFile, just the ones I tell it to
write.  Is there any hope of achieving this, or is it not the intended
use for a TFile?  Is there a better approach?  It's a bit confusing
(though I did read an old roottalk thread about TFiles, and that
helped some).

Thanks for any info,
Reid

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