[Interest] QFile::write(const QByteArray&) does not write all data?

[Helmut Mülner]

Are you sure your QByteArray has the correct size?
If your constructed it from a const char* and did not give the size, it may
contain only data up to the first zero byte.

helmut

-----Ursprüngliche Nachricht-----
Von: Interest
[mailto:interest-bounces+helmut.muelner=gmail.com at qt-project.org] Im Auftrag
von alexander golks
Gesendet: Mittwoch, 9. Mai 2018 11:40
An: interest at qt-project.org
Betreff: Re: [Interest] QFile::write(const QByteArray&) does not write all
data?

Am Wed, 09 May 2018 09:24:58 +0000
schrieb Vadim Peretokin <vperetokin at gmail.com>:

yes, i tried flushing the file, too. but this changed nothing.

i now have same do while loop as in
  qint64 QFSFileEnginePrivate::nativeWrite(const char *data, qint64 len) and
this works. this writes complete file.

but i think, QFile implementation is wrong here.
i think nativeWrite should set error and return -1 on every chunk, not only
at first chunk.

alex

> Obvious question but do you flush?
> 
> On Wed, May 9, 2018 at 11:09 AM alexander golks <alex at golks.de> wrote:
> 
> > hi,
> >
> > i recently stumbled over this situation, running on windows 7 using 
> > qt-5.6.3.
> > when trying to write ~50MB of data, write does not always complete, 
> > the file does not contain all data, yet no error is returned.
> >
> > i always thought, QFile::write(const QByteArray&) is meant to write 
> > all data.
> > as stated in the documentation for: qint64 
> > QIODevice::writeData(const char *data, qint64 maxSize) "When 
> > reimplementing this function it is important that this function 
> > writes all the data available before returning."
> >
> > is this a bug in QFile?
> > or do i have to do-while loop to write the rest of my data?
> > but wouldn't this lead missing writes in QDataStream + QFile, as 
> > QDataStream needs complete writes, too?
> >
> > alex
> >
> > --
> > /*
> >  *  Learn to pause -- or nothing worthwhile can catch up to you.
> >  */
> > _______________________________________________
> > Interest mailing list
> > Interest at qt-project.org
> > http://lists.qt-project.org/mailman/listinfo/interest
> >  


--
/*
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