I need to create a windows service that will monitor a directory for newly uploaded files. The files will be around 100K to 400K in size.
Is there a chance that my monitoring system will notice a new file, but the file hasn't completetly finished copying over? i.e. it is still streaming in and the EOF hasn't been written yet?
Yes, there is a chance that this will happen. You should upload the file to a temporary directory first, then move it to the directory you're monitoring when the entire file is present on your file system.
Try reading the second tale here and the comments. Essentially, it's as Bill the Lizard said
yes. With small files the risk is fairly low, but if you want to be certain have it check when it sees a file to make sure it's size stays stable over a second or two.
Are you using a FileSystemWatcher? I've only used this once, but I think you can configure the parameters to tell it what events you want to consider and set up separate handlers for each. I suspect that the FileSystemWatcher may not even notify you on file creation until the file has been closed, but I haven't tried it.
Note: this is .NET solution. If you're not using .NET, please disregard.
