Transactional file writing in C# and Windows?

Question

I have a data file and from time to time I need to write a change to the file. The change consists of changing information in more than one place. For example, changing some

Answer 1

If you are using Windows 6 or later (Vista/7/2008/2008R2) the NTFS filesystem supports transactions (including within a distributed transaction): but you will need to use P/Invoke to call Win32 APIs (see this question).

If you need to run on older versions of Windows, or non-NTFS partitions you would need to perform the transactions yourself. This is decidedly non-trivial: getting full ACID functionality while handling multiple processes (including remote access via shares) across process and system crashes even with the assumption that only your access methods will be used (some other process using normal Win32 APIs would of course break things).

In this case a database will almost certainly be easier: there are a number of in-process databases (SQL Compact Edition, SQL Lite, ...) so a database doesn't require a server process.