in reply to
Re: how to tell if a file is still being modified
in thread how to tell if a file is still being modified
That scheme is inefficient and fragile. Why bother to read the entire file and calculate a hash on it, when checking the file size is a whole lot faster and for an FTP upload, is just as good?
It is fragile; imagine what would happen if the upload stalled for X+1 seconds and then resumed. If you make X large to try to avoid this, it makes the processing slower.
The permission bits scheme is better, if your system supports permission bits.