C++/Win32: How to wait for a pending delete to complete

Silly suggestion - since it fails so infrequently, simply wait some milliseconds on failure and try again.

Or, if latency is important, switch to another file name, leaving the old file to be deleted later.

First rename the file to be deleted, and then delete it.

Use GetTempFileName() to obtain a unique name, and then use MoveFile() to rename the file. Then delete the renamed file. If the actual deletion is indeed asynchronous and might conflict with the creation of the same file (as your tests seems to indicate), this should solve the problem.

Of course, if your analysis is right and file operations happen somewhat asynchronous, this might introduce the problem that you attempt to delete the file before the renaming is done. But then you could always keep trying to delete in a background thread.

If Hans is right (and I'm inclined to believe his analysis), then moving might not really help, because you might not be able to actually rename a file that's open by another process. (But then you might, I don't know this.) If that's indeed the case, the only other way I can come up with is "keep trying". You would have to wait for a few milliseconds and retry. Keep a timeout to give up when this doesn't help.

There are other processes in Windows that want a piece of that file. The search indexer is an obvious candidate. Or a virus scanner. They'll open the file for full sharing, including FILE_SHARE_DELETE, so that other processes aren't heavily affected by them opening the file.

That usually works out well, unless you create/write/delete at a high rate. The delete will succeed but the file cannot disappear from the file system until the last handle to it got closed. The handle held by, say, the search indexer. Any program that tries to open that pending-delete file will be slapped by error 5.

This is otherwise a generic problem on a multitasking operating system, you cannot know what other process might want to mess with your files. Your usage pattern seems unusual, review that first. A workaround would be to catch the error, sleep and try again. Or moving the file into the recycle bin with SHFileOperation().