Hi, On Wed, 22 Mar 2017, Karoly Balogh (Charlie/SGR) wrote:
> However, please note that transactional file handling on power loss is a > quite delicate scenario, so you might not be able to solve all the related > problems with this - what happens exactly when you get a power loss during > a write, might be matter of pure luck. > > The usual way to work this problem around on Linux systems at least, is to > write a new file, then do an overwriting rename to the old file name. > There rename is an "atomic" operation, which will be either committed to > the disk or not, but if it was unsuccessful, you won't end up with > half-written files. But IIRC Windows didn't support atomic renames. Maybe > someone with more Windows knowledge will fix me. You definitely don't want > to implement a copy though, and that's anything but atomic. Actually, this blogpost which I've just found also details the algorithm how you should do it, from a Windows perspective: https://blogs.msdn.microsoft.com/adioltean/2005/12/28/how-to-do-atomic-writes-in-a-file/ Charlie _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
