[slang-users] SLAG update and information.

[Paul Boekholt]

On Fri, 05 Aug 2005 13:48:58 -0500, Ben Duncan <ben at versaccounting.com> said:

> Ok, first kudo's for Paul for writing the tdb interface.

> Unfortunately I have discovered a severe limit in tdb in that it allows
> only one open for each file per process ID.
You can open and close a file multiple times, but you can't open it,
keep it open and then open the same file again, that's right.   GDBM
can't do that either - actually it can on Linux, but I think it's a
bug.  It's probably OK to open a GDBM file multiple times read-only
though.

> Accounting programs usually can and do have the files open multiple
> times (And A/R aging routine is a prime example).
Can you expand on this?  Does A/R aging open a file multiple times
read-only, or read/write? 


> Now all I have to do is come up with a embedded database engine for SLAG.
> I am looking at possible adapting GDBM to a Multi Value environment and use my
> own locking semaphore routines.
What OS does the Department of Wildlife use?  If they use windows,
you probably can't use tdb.  If you need to open a file multiple times
read-only in one process, then if you don't need concurrency, use GDBM.
Otherwise, ask the tdb maintainers to fix it (maybe it's already fixed
in the Samba version?).  If you need to open a file multiple times
read-write in one process, you should look for some other database.  If
you don't need to open a file multiple times read-write in one process,
but you do need concurrency, then try to get the Department of Wildlife
to switch to Linux, or try to get someone to port tdb to Windows.