Subject: Re: [boost] Making Boost.Filesystem work with GENERAL filenames with g++ in Windows (a solution)
From: Artyom Beilis (artyomtnk_at_[hidden])
Date: 2011-10-26 05:47:39
----- Original Message -----
> From: Alf P. Steinbach <alf.p.steinbach+usenet_at_[hidden]>
> First, apologies if I'm posting to the wrong group/list; if so then please
> redirect me.
> IMHO access to files is a crucial part of Boost.Filesystem. However, with Boost
> 1.47, and using g++ 4.4.1 in Windows 7, boost::filesystem::ifstream etc. fail to
> open or create files with non-ANSI characters. It works fine with Visual C++; it
> FAILS with g++ 4.4.1, which is the one bundled with the Code::Blocks IDE.
> The failure probably has nothing to do with the g++ version: it's due to g++
> not offering the Visual C++ wchar_t oriented extensions to the standard
> iostreams (Boost.Filesystem uses these Visual C++ extensions).
> I stumbled onto this while I was writing about using Unicode in C++ programming
> in Windows.
Why just not to implement boost::filesystem::fstream over _wfopen and custom
It is relatively simple.
I have implemented such thing under booster namespace as part of cppcms project
> I wrote up a technical solution in section 5, starting on page 16, of that
> work-in-progress document, available on Google Docs at:
> Essentially, the fix I ended up with, full source code given in the above doc,
> uses Windows short file names if (1) there is no wide character support and if
> furthermore (2) the filename can't be perfectly translated to ANSI. The C++
> implementation's support for wide chars is automatically detected using
> C++98-compatible code.
> I do not know what to do with this.
That is what very good about stream buffers... You can implement anything
Using short file names is no go for two reasons:
1. It works only when file exists (can't create new file)
2. It is quite deprecated
> But considering that Boost.Filesystem is slated for later inclusion in the C++
> standard library (or at least into TR2), I think it would be nice if it is able
> to give access to all accessible files in Windows, also with g++,
This is a problem that can be fixed easily in Boost.Filesystem.
> so that we
> don't end up with a file handling part of the standard library that
> can't handle files in general;
This is a "bug" in Windows operating system... but this is other story.
> hence this posting and plea for advice --
> what more should I do, if anything?
Write a patch that implements stream buffer over stdio and _wfopen?
> - Alf
CppCMS - C++ Web Framework: http://cppcms.sf.net/
CppDB - C++ SQL Connectivity: http://cppcms.sf.net/sql/cppdb/>
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