”Log files. Append-only mode, enforced. Can't seek back and overwrite. On a crash, the file recovers to some recent good write, with a correct end of file position. It does not tail off into junk.“
As wahern says, append-only is available in some OSes. I am not aware of any that guarantees the “recovers to some recent good write” part, though. UNIX-like OSes won’t support it, as they don’t have a way to write more than one byte atomically (https://en.wikipedia.org/wiki/Write_(system_call): The write function returns the number of bytes successfully written into the array, which may at times be less than the specified nbytes)
As wahern says, append-only is available in some OSes. I am not aware of any that guarantees the “recovers to some recent good write” part, though. UNIX-like OSes won’t support it, as they don’t have a way to write more than one byte atomically (https://en.wikipedia.org/wiki/Write_(system_call): The write function returns the number of bytes successfully written into the array, which may at times be less than the specified nbytes)