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[LDM #EQT-156607]: pqsurf bailing on ldm 6.4.2

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  • Subject: [LDM #EQT-156607]: pqsurf bailing on ldm 6.4.2
  • Date: Wed, 01 Feb 2006 11:00:22 -0700
Well, today I learned something new.

It appears that the LDM hasn't included the GDBM package for many years but has
, instead, required user's that wanted the DBFILE action to have a GDBM library
 already installed.  I think this was done because the only users of the DBFILE
 action were user's of Peter Neilley's WEATHER package.  I only learned about i
t now because this is the first time it's come-up since I took over the LDM pac
kage a few years ago.

It also appears that the GDBM library has a bug.  A stack trace of one of the p
qact(1) core files in the LDM user's home-directory on mist.met.tamu.edu shows 
the following:

(gdb) where
#0  0x4207afcc in chunk_free () from /lib/i686/libc.so.6
#1  0x4207ad24 in free () from /lib/i686/libc.so.6
#2  0x40050a4c in gdbm_close () from /usr/lib/libgdbm.so.2
#3  0x0804b7c8 in ldmdb_close ()
#4  0x08049fae in free_fl_entry ()
#5  0x0804a0c2 in delete_entry ()
#6  0x0804a15c in close_lru ()
#7  0x0804dc76 in main ()
#8  0x42017589 in __libc_start_main () from /lib/i686/libc.so.6

So, it looks like calling the GDBM function gdbm_close() resulted in a segmenta
tion violation.  It's extremely unlikely that the pqact(1) program is indirectl
y causing this problem because the same code that the pqact program uses for th
e DBFILE action is also used by the FILE and STDIOFILE actions, and they've nev
er had a problem.

I'm afraid I don't know what to tell you, Neil.  Debugging the 3rd-party GDBM p
ackage is beyond my purview.  You might try adding a "-close" option to the DBF
ILE action.  You might also try deleting the GDBM  files and starting from scra
tch.  It could be that the bug won't manifest itself again for years if that's 
done.  You might also try posting to the <address@hidden> mailing-
list to see if anyone else has encountered this problem.

I'll also ask around here to see what alternatives exist to using the WEATHER p
ackage.

I'm sorry I can't be more positive.  Good luck.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: EQT-156607
Department: Support LDM
Priority: Normal
Status: Open