Re: [PATCH v2 3/3] compat/mingw: support POSIX semantics for atomic renames

> On Sun, Oct 27, 2024 at 02:23:28PM +0100, Johannes Sixt wrote:
>> Am 24.10.24 um 13:46 schrieb Patrick Steinhardt:
>>> Windows 10 has introduced the `FILE_RENAME_FLAG_POSIX_SEMANTICS` flag
>>> that allows us to fix this usecase [1]. When set, it is possible to
>>> rename a file over a preexisting file even when the target file still
>>> has handles open. Those handles must have been opened with the
>>> `FILE_SHARE_DELETE` flag, which we have ensured in the preceding
>>> commits.
>>>> Careful readers might have noticed that [1] does not mention the above
>>> flag, but instead mentions `FILE_RENAME_POSIX_SEMANTICS`. This flag is
>>> not for use with `SetFileInformationByHandle()` though, which is what we
>>> use. And while the `FILE_RENAME_FLAG_POSIX_SEMANTICS` flag exists, it is
>>> not documented on [2] or anywhere else as far as I can tell.
>>
>> The Windows 10 SDK defines FILE_RENAME_FLAG_REPLACE_IF_EXISTS and
>> FILE_RENAME_FLAG_POSIX_SEMANTICS for SetFileInformationByHandle(). That
>> the documentation lacks "_FLAG_" in the names must be an error in the
>> documentation.
>>
>> I found the mention of FILE_RENAME_POSIX_SEMANTICS quite distracting,
>> because it is a flag to be used with CreateFileW() and basically only
>> has to do with case-sensitivity, but nothing with POSIX semantics of
>> renaming.
> 
> I'd still prefer to mention this, because otherwise an astute reader
> might notice that I'm using a different flag name than what is
> documented in the docs and figure out that I defined the wrong flag
> name.