Thread

1. Large Object / libPQ : problem

   Chris <linux.fellow@libertysurf.fr> — 2000-08-19T22:41:34Z

   Hi, all.
   
   I'm encoutering a problem with libpq when opening a large object.
   If I use lo_import within psql, there's no problem. But when I use
   the libpq functions 'lo_open', the function fails. (also, lo_import
   fails
   in the call to lo_open.) After some experiments, I found that the
   lo_open
   function seemed to work at open-time, but it's calling 'lo_lseek' just
   after,
   and that seems not to work. (invalid descriptor 0).
   
   This causes many problems, coz I really need that functionnality. (as
   'Binary'
   type is not yet implemented... and would be quite the same !)
   
   
   
   Infos :
   
     System: Linux 2.2.x (with libc GLibc 2.1.3)
     Arch: Intel x86 (AMB K6-II and AMD Athlon)
     CC: gcc (tryed both pgcc and gcc 2.98)
     PostgreSQL: postgres-7.0.2
   
   
   
   [note: I found a message that seemes to show a similar problem in the
   base, it
   was posted by Alexey Kobozev]
   
   

2. Re: Large Object / libPQ : problem

   Tom Lane <tgl@sss.pgh.pa.us> — 2000-08-20T02:49:40Z

   Chris <linux.fellow@libertysurf.fr> writes:
   > the libpq functions 'lo_open', the function fails. (also, lo_import
   > fails in the call to lo_open.) After some experiments, I found that
   > the lo_open function seemed to work at open-time, but it's calling
   > 'lo_lseek' just after, and that seems not to work.
   
   It sounds like you are neglecting to wrap the whole process in a
   transaction block (BEGIN/COMMIT).  The LO handle returned by lo_open
   is valid only as long as you keep the current transaction open.
   
   			regards, tom lane