I am in change of maintaining a legacy system running on AIX 4.2
which uses a Sybase 11.5.1 database server as it's back end and
an old Sybase text based windowing system called APT as it's
front end. APT has been out of support since 2000.

I am migrating the system to a new box with a Sybase 12.5.3
server running on AIX 5.2.

This went pretty well, and we are doing final testing this week.

But today I have encountered a problem with the way values
(drop down) lists on APT form fields, are dealt with by APT
on Sybase 12.5.3 / AIX 5.2

On the new 12.5.3 box, if the CTRL-V query or called stored
procedure returns more than 250 rows then the APT window hangs.
It generates the list in the CTRL-V fine, but when you press on
ENTER to select one it hangs at that point.

I worked out the 250 rowcount by trial and error using a single
sp called from a CTRL-V and reducing the rowcount down, until
APT no longer hung.

As I no longer have the APT setup / installation CDs (or manuals
either!) I copied over the /home/sybapt directory to the new box,
so it's setup is exactly the same as on the old one.

I think my problem is caused by a buffer overrun of some sort.

The amount of memory allocated to an APT session does not appear
to be configurable, so I am thinking that it picks up some AIX system
default for user memory usage which may be different between
4.2.1 and 5.2.

Can anyone suggest what this setting or settings might be?

I'm open to other suggestions! Anyone got any ideas?

Tom.