Re: [Boost-users] [boost] [interprocess] Semaphore cleanup after crash

From: Sachin Garg (schngrg_at_[hidden])
Date: 2008-08-02 04:40:46

On Sat, Aug 2, 2008 at 1:48 PM, Ion Gaztañaga <igaztanaga_at_[hidden]> wrote:
> Ion Gaztañaga wrote:
>>
>> The same problem with files and I haven't seen any clue to make Unix and
>> Windows behavior identical until today:
>>
>> http://mg.to/2004/09/30/file_share_delete-in-shell-extension
>>
>> According to this, adding FILE_SHARE_DELETE to the shared memory emulation
>> functions would allow, UNIX-like behavior for Windows files. I  haven't had
>> time to test this.
>
> I've just checked this, but it does not behave like unix. If you specify
> FILE_SHARE_DELETE you DeleteFile returns success when the file when it's in
> use (but the file it's still there in the explorer) and opening the file
> after deletion fails. However, if you try to create another file with the
> same name this also fails. So you can't just call "remove" and recreate the
> file with the same name. That's a pity.

If you are at making behavior identical, I would much prefer the
windows way rather than posix way. Not a preference towards any
platform, just that the windows way seems to make more sense. Or maybe
two 'removes', one which works as it does now and other the
smart_remove. In case someone out there does prefer's posix way.

Of course, I don't have any answer as to how to get either done.

I have been trying to hack in Bob's solution in my code as it can work
atleast for me. But its painful as internal implementation of
named_semaphore is different on win/lin/mac, so both lin and mac will
need separate hacks, and then this is something that will need to be
carefully examined again every time boost is updated as internal
implementations may change is future. Sometimes I just wish things
were easier :-)

Sachin Garg