knowing when file is flushed to disk

[John Pote]

Thanks for the replies. I guessed the situation would be flush() and trust. 
The probability of a crash between flush() returning and data actually 
written resulting in a trashed disk must be very small. But if you can be 
certain without too much effort it's got to be a good idea, so I thought I'd 
ask anyway.

How does the banking industry handle this sort of thing? Could be big bucks 
if something goes wrong for them!

Thanks again,

John