[Interest] QTemporaryFile::open(OpenMode flags) is protected, but not in documentation

[Constantin Makshin]

It's used exactly for that purpose -- storing large amounts of temporary
data which doesn't need super-low access times (so there's no need to waste
RAM). You can do whatever you like with that data, just don't close the
file. And, to be honest, I don't see any [good] reason to close a temporary
file (regardless of the implementation) if you're going to access it again,
particularly for the reason mentioned by Thiago -- closing a file means
losing any control over its contents, there are absolutely no guarantees
that the next time you open the "same" file (when actually that'll be a
file with the same path), you'll see the same data you wrote to it earlier.
On Sep 26, 2013 12:57 PM, "Etienne Sandré-Chardonnal" <
etienne.sandre at m4x.org> wrote:

> Hi Thiago,
>
> Then I don't see the point of QTemporaryFile... You write some data and
> can't do anything with it?
>
> What are the legacy uses of it?
>  - Open the file with a QFile for reading. Such use would be a large
> buffer we do not want to keep in memory. But according to what you said, it
> must be done before the QTemporaryFile was closed. Then, what guarantees
> the writes have been flushed?
>  - Write data to a temporary file before renaming it to the final name.
> This is useful when a user saves a document overwriting the old version, in
> case the system or app crashes he does not loose all the work. But
> QFile::rename() closes before renaming, which means according to what you
> said the data is not guaranteed to be still there.
>
> I definitely need some additionnal explanation to the documentation on how
> to use this class
>
> Etienne
>
>
> 2013/9/26 Thiago Macieira <thiago.macieira at intel.com>
>
>> Once you close the file, your data is gone. Your data only exists as long
>> as
>> you keep the file open.
>>
>
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