FreeTDS Development Group

[Michael Peppler <mpeppler AT peppler.org>]

Brian Bruns writes:
 > 
 > 
 > On Wed, 25 Aug 1999, Mark Schaal wrote:
 > 
 > > > 
 > > > Mark Schaal writes:
 > > >  > >
 > > >  > > Actually that's changed and checked in.  I found the same 
 > > > thing...but I
 > > >  > > still get main.t to crash.  That's against a Sybase 11.x server 
 > > > (the JDBC
 > > >  > > server at Sybase)
 > > >  > > 
 > > >  > > Brian
 > > >  > 
 > > >  > I think you should be saving the data in the buffer and not the 
 > > > buffer
 > > >  > itself.  I could be wrong...
 > > > 
 > > > I don't think so.
 > > > 
 > > > I sort of figured that you only store the pointer to the buffer that
 > > > is passed in, and it's length. Otherwise, when the app changes the
 > > > data in that buffer it won't be reflected in the CS_USERDATA buffer.
 > > > 
 > > > Michael
 > > 
 > > <*sigh*> If only we had ctlib documentation.
 > >
 > 
 > I've got dblib/cslib/ctlib/server lib manuals :P
 > 
 > Seriously, you can go to sybooks.sybase.com and all the manuals are on
 > line, although sqml to html garbage they use is slow enough to drive you
 > crazy.
 > 
 > The doc states *buffer is 'user allocated data'.  Although a little vague
 > it seems to indicate that the user is responsible for keeping the data
 > and releasing it...If I was at work I could test it fairly simply, just
 > store it change it and then ask for it back.

I think so. And it's similar to the dbsetuserdata() call in the DBlib
side. I think the explanation of the dbsetuserdata() functionality
(and teh deadlock example code that is included there) explains this
functionality well.

In DBD::Sybase I definitely expect the buffer returned by the
CS_USERDATA property to be the same buffer that I passed in earlier -
its elements can change and the action I take in the server or client
callbacks depend on those values (typically whether to call a perl
callback from the C error handler or not).

Michael
-- 
Michael Peppler         -||-  Data Migrations Inc.
mpeppler AT peppler.org    -||-  http://www.mbay.net/~mpeppler
Int. Sybase User Group  -||-  http://www.isug.com
Sybase on Linux mailing list: ase-linux-list AT isug.com