/*
 * call-seq:
 *    lrg.seek( offset, whence )
 *
 * Move the large object pointer to the _offset_.
 * Valid values for _whence_ are +SEEK_SET+, +SEEK_CUR+, and +SEEK_END+.
 * (Or 0, 1, or 2.)
 */
static VALUE
pglarge_seek(obj, offset, whence)
  VALUE obj, offset, whence;
{
  PGlarge *pglarge = get_pglarge(obj);
  int ret;
  
  if((ret = lo_lseek(pglarge->pgconn, pglarge->lo_fd, NUM2INT(offset), NUM2INT(whence))) == -1) {
  rb_raise(rb_ePGError, "error while moving cursor");
  }

  return INT2NUM(ret);
}