Re: Win32 rename()/unlink() questions

I don't think we are not going to be supporting Win9X so there isn't an
issue there. We will be supporting Win2000/NT/XP.

I don't understand FILE_SHARE_DELETE. I read the description at:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/createfile.asp

but I don't understand it:

FILE_SHARE_DELETE - Windows NT/2000/XP: Subsequent open operations on
the object will succeed only if delete access is requested.

---------------------------------------------------------------------------

Mike Mascari wrote:
> Stephan Szabo wrote:
> > On Fri, 20 Sep 2002, Mike Mascari wrote:
> >>
> >>Yes! Indeed that does work.
> >
> >
> > Thinking back, I think that may still fail on Win95 (using MoveFile).
> > Once in the past I had to work on (un)installers for Win* and I
> > vaguely remember Win95 being more strict than Win98 but that may just
> > have been with moving the executable you're currently running.
>
> Well, here's the test:
>
> foo.txt contains "This is FOO!"
> bar.txt contains "This is BAR!"
>
> Process 1 opens foo.txt
> Process 2 opens foo.txt
> Process 1 sleeps 7.5 seconds
> Process 2 sleeps 15 seconds
> Process 1 uses MoveFile() to rename "foo.txt" to "foo2.txt"
> Process 1 uses MoveFile() to rename "bar.txt" to "foo.txt"
> Process 1 uses DeleteFile() to remove "foo2.txt"
> Process 2 awakens and displays "This is FOO!"
>
> On the filesystem, we then have:
>
> foo.txt containing "This is BAR!"
>
> The good news is that this works fine under NT 4 using just
> MoveFile(). The bad news is that it requires the files be opened
> using CreateFile() with the FILE_SHARE_DELETE flag set. The C
> library which ships with Visual C++ 6 ultimately calls
> CreateFile() via fopen() but with no opportunity through the
> standard C library routines to use the FILE_SHARE_DELETE flag.
> And the FILE_SHARE_DELETE flag cannot be used under Windows
> 95/98 (Bad Parameter). Which means, on those platforms, there
> still doesn't appear to be a solution. Under NT/XP/2K,
> AllocateFile() will have to modified to call CreateFile()
> instead of fopen(). I'm not sure about ME, but I suspect it
> behaves similarly to 95/98.
>
> Mike Mascari
> mascarm(at)mascari(dot)com
>
>
>
>
>
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