Re: [Boost-users] Boost.Iostreams: mapped_file_sourcecan'topenreadonly files

From: Jonathan Turkanis (technews_at_[hidden])
Date: 2005-08-29 15:14:27

Elisha Berns wrote:
> Jonathan,
>
> Thanks for the reply.  I have found a fix for this problem.  It
> consists of two things:
>
> 1) A small code change in mapped_file.cpp to make extra sure the
> correct flag is set:
>
> //--------------Open underlying
> file------------------------------------ 
>
>     pimpl_->handle_ =
>         ::CreateFileA( p.path.c_str(),
>              readonly ? GENERIC_READ : GENERIC_ALL,
>              FILE_SHARE_READ,
>              NULL,
>              (p.new_file_size != 0 && !readonly) ?
>                   CREATE_ALWAYS :
>                   OPEN_EXISTING,
>              readonly ? FILE_ATTRIBUTE_READONLY :
> FILE_ATTRIBUTE_TEMPORARY,
>               NULL );
>
>     if (pimpl_->handle_ == INVALID_HANDLE_VALUE)
>         detail::cleanup_and_throw(*pimpl_, "failed opening file");
>
> it's the line:
>
> readonly ? FILE_ATTRIBUTE_READONLY : FILE_ATTRIBUTE_TEMPORARY,

To be honest, I'm not sure I understand why FILE_ATTRIBUTE_TEMPORARY is used
here. I think Jonathan Graehl suggested it. Could you see if your code works
with FILE_ATTRIBUTE_NORMAL?

> 2) My apologies about this second thing, since it's my problem, even
> if it is an issue of checking under the hood what assumptions are
> made by Boost.Iostreams.  The issue is that the file names that I get
> from XercesC contain a mix of forward slashes and back slashes for
> directory separators.  In Win32, the file mapping API
> CreateFileMapping doesn't accept back slashes except in a few cases.

This has been fixed in CVS.

Thanks.

Jonathan