Scott Hochberg wrote:

> When I updated to FB4 from FB2 in order to be able to provide my  
> apps for OS X, I found that my routine for opening user files  
> failed for a small number of users.  Since I couldn't replicate the  
> issue, I tried some cookbook cut and paste and added FN FbwdToPbwd  
> (PBlk&) just before my FN PBHOpenAsync command, as was mentioned in  
> one of the FB conversion help files.
>
> That worked for those customers when they were opening the file for  
> input, but broke when they were opening a different file for  
> output.  So I fixed that by making it conditional for just the  
> open, which is also the first occurrence.
>
> Since most of the customers did not have the problem in the first  
> place, I resisted including this change in my public release of the  
> product (for fear I would cause more problems than I solved.)  But,  
> after updating that release to make some other changes, additional  
> customers reported the problem, even though I did not change  
> anything in that portion of the code. Again, the problem was fixed  
> when I made the change discussed above.
>
> So I think I now have my customers' problems solved, but I don't  
> understand what the line I added did, and why it would be necessary  
> for apparently random users (some but not all OS 8, 9, X), and why  
> this function didn't cause a problem for those whose software was  
> working correctly without it.

Do you provide a completion routine for PBHOpenAsync? If not, then  
you should be calling PBHOpenSync instead.

Robert P.