I'm not familiar with the implementations of OS disk caching, but it seems to me there's no guarantee that any but the last call to overwrite_file makes it to disk from the system's cache. Even then... With a particularly good cache, absolutely nothing would be written to disk.

Remember, sys* disables user-land caching. It doesn't prevent OS caching. FILE_FLAG_NO_BUFFERING would do that in Windows, but I see no reference to it in win32/win32io.c in perl.git.

In reply to Re: overwrite a file by ikegami
in thread overwrite a file by jdporter

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