Can't run Informix 4GL Interactive Debugger

Question

I am reading through Informix 4GL By Example. Ex4 is giving a segmentation fault so I am attempting to use the debugger to find out where the program is failing, but the debugger is not working.

From within r4gl, I can compile forms and modules. But when I debug it shows a blank screen with "Press Return to continue".

From the command line fgldb returns the following error:

fgldb: symbol lookup error: fgldb: undefined symbol: kw__numkws

DB is up and running, I can isql in and run queries.

System details:

• OpenSuSE 12.1 32 bit
• Informix RDS 7.50 UC6
• Informix SQL DEV 7.50 UC6
• Informix Growth Edition 11.70 UC5
• Informix Interactive Debugger 7.50 UC6

I have searched the net, but have not found anything helpful. Any idea what's wrong?

UPDATE 1:

Thank you again for the assistance. I will be trying to install in a seperate directory and let you know. This is probably blonde but how do I install in a different directory. If I attempt to I get errors:

"INFORMIXDIR and working directory do not match." "INFORMIXDIR = /usr/informix" "Current working directory = /usr/informix/i4gl"

Can I edit $INFORMIXDIR to match where I want to install?

Many thanks,

Neill

UPDATE 2:

OK, so I got them both installed in /usr/informix/i4gl.

Set variables to point to that directory, not sure exactly which ones need to though because I still receive errors.

1. fgldb: -16326: Cannot open file 'fgldb.iem'

The /usr/informix/i4gl does contain a directory msg/en_us/0333, but that file does not exist there, while /usr/informix/msg/en_us/0333 does include the fgldb.iem file.

1. isql -> Query Language: Says SELECT DATABASE, but none or shown for me to select.

Kind regards

Neill

UPDATE 3:

OK, my blonde momnets are getting crazy now, but after installing into /usr/informix/i4gl, I never changed back the $INFORMIXDIR variable. I did this and then stopped and started the DB.

Now when trying to compile the demo f_custkey.per (using stores_demo db as before) form, I get errors -329 and -2810, which are to do with the database not found.

I am not sure if this is what you were talking about in your last statement. I am unsure if splitting these two into seperate directories has solved my debugger issue because now I can't compile anything, but I sense I am getting close.

Kind regards,

Neill

UPDATE 4 - Final!

OK, so it is working now.

Ran the dbaccessdemo7 command again to recreate the database and all is well in the land of nod.

Compiling and debugging ex4 now works.

Thank you so much for all the information. Learning as I go.

Kind regards

Neill

Answer 1

The core dump/crash that you're hitting is an unfortunate bug that we found out about earlier this week. The ESQL/C code is fixed (as of today), but the fixed releases are not yet available, and won't be for a while (read 'until after Thanksgiving at the earliest'). The I4GL and ISQL code still has to be fixed (some separate, but closely related problems).

What's happened is that a structure changed size in the CSDK. I4GL will be compiling the code with the one size and the CSDK libraries are expecting another size; the difference is about 4 bytes. This leads to hard to track memory overwriting.

The kw__numkws issue is an older problem that I thought was fixed in 7.50.UC6. I'll have to check whether that release did get the fix, and if so, how you are seeing that error still.

There are a couple of short-term options that should get you going until a fixed ensemble is available:

1. Reinstall I4GL (and ISQL) in the server directory. I've not proved that this will work. The concept is to make sure I4GL is using the CSDK libraries it was built with, rather than the updated 3.70.xC6 version.

2. Reinstall I4GL (and ISQL) in a separate directory (/opt/IBM/i4gl, perhaps). Have a suitable sqlhosts file in this directory; it might be a symlink to the one in the IDS directory. Point the I4GL programs at this alternative directory, setting LD_LIBRARY_PATH appropriately.

Option 2 ensures that I4GL is using the 'correct' CSDK. Option 1 may achieve the same result, but I'm not ready to guarantee it. Consequently, I suggest option 2.

If your I4GL code needs to run DB-Access or other programs found in the server $INFORMIXDIR, there are ways to deal with that — indicate in a comment and I'll explain, but I'd rather not confound you if there's no need. (It's not dreadfully hard, but it isn't completely trivial either.)

Answer 2

The kw_numkws issue is fixed post 7.50.UC6. So the next available fixpack will have the fix. In the interim, IBM Technical Support has posted a "Tech Alert" advising customers to install I4GL (and ISQL) in a separate directory - option #2 suggested by Jonathan Leffler above.

Answer 3

Option 3. is to discover what CSDK was used to create the 4GL tools and install THAT instead of the current one. In the case of 4GL 7.50FC6 it CSDK 3.70FC4.

I had problems splitting up the engine and the tools. This appears to work, so far.