Lock File but My app still can read it?

[user]

Let's say my app require a file. While my app actives in memory, I want to lock the file from being deleted and my app still can read the content of the file. I don't want to use LockFile API because every time my app read the file, it have to unlock the file (with UnlockFile), considering my app is a multi-threading app.

I won't store the content of file into memory, it will consume much memory. I wonder if there is any tricks or other API to solve my issue? No malicious way!