Posted by Tom Fulton on October 18, 2006 at 08:35:53:
The first version of our Document-Imaging system relied on using the
ODBC Gateway to a MySQL Database. Our current version makes use of
PDF Images of the documents. On the original version we have been
having occasional problems with users reporting the nondescript EXCP
29. I have finally made some progress on this issue that sheds some
light.
The user addresses leading up to the Excp 29 wind up on the following
code:
close (30)
open (30) Gate$ ! where Gate$ is a valid ODBC Gateway
The last address is the address of the OPEN. My forms program simply
GOSUBS this routine that came from Brian's library, OpenGateWay:, and
goes on its merry way. I decided to put an ENTER immediately before
the GOSUB OpenGateWay. This ENTER program would do a couple of tests
for me, first it would do an identical OpenGateWay and second it did
a dbOpen to see if the ODBC Datasource was configured. Any error would be trapped and displayed. When I put this ENTER into my forms
program, I started getting the EXCP 29! Interesting... When I removed the ENTER program, no EXCP 29. Hmmm, to keep testing things I put a close on LUN (30) right after the dbClose in my ENTER program. When I did this, no EXCP 29 was generated. So, my conclusion is that there is some timing issue between the close of the ODBC Gateway LUN and the open, and that the EXCP 29 is, in reality, some form of an Exception 34. My remedy is that I am going to add a PAUSE (18)
before: Close (ODBCORD) & Open (ODBCORD) Gate$
after: Close (ODBCORD) & PAUSE (18) & Open (ODBCORD) Gate$
and also to add a Close (ODBCORD) immediately after my dbClose. I'll post results up in a week or two. Tom.