Ansi vs Unicode API

[Denis Koroskin]

On Mon, 16 Nov 2009 11:56:24 +0300, Andrei Alexandrescu
<SeeWebsiteForEmail at erdani.org> wrote:

> Denis Koroskin wrote:
>> I'd like to raise 2 issues for a discussion.
>>  First, Phobos makes calls to different functions, based on the OS we  
>> are running on (e.g. CreateFileA vs. CreateFileW) and I wonder if it's  
>> *really* necessary, since Microsoft has a Unicode Layer for those  
>> Operating Systems.
>>  All an application needs to do to call W API on those OS'es is link  
>> with unicows.lib (which could be a part of Phobos). It does nothing on  
>> Win2k+ and only triggers on 9x OS family.
>>  A very good overview of it is written here:
>> http://msdn.microsoft.com/en-us/goglobal/bb688166.aspx
>>  Second, "A" API accepts ansi strings as parameters, not UTF-8 strings.  
>> I think this should be reflected in the function signatures, since D  
>> encourages distinguishing between UTF-8 and ANSI strings and not store  
>> the latter as char[].
>>  LPCSTR currently resolves to char*/const(char)*, but it could be  
>> better for it to be an alias to ubyte*/const(ubyte)* so that user  
>> couldn't pass unicode string to an API that doesn't expect one. The  
>> same is applicable to other APIs, too, for example, how does C stdlib  
>> co-operate with Unicode? I.e. is core.stdc.stdio.fopen() unicode-aware?
>>  What are your thoughts on the subject?
>
> I think it's a great idea. Can phobos redistribute the unicows.lib (cute  
> name)?
>
> Andrei

A quote, first:

> MSLU comes with licensing terms that are highly unfriendly to Open Source
> applications: although you can freely distribute unicows.dll with your
> application, your licensing terms must meet certain > conditions that no
> Open Source license can. Namely, you must forbid further redistribution
> and the license must be an EULA accepted by the user either in writing
> or using click-through or shrink-wrap mechanism.
> To overcome this obstancle, the Mozilla project began reimplementing
> similar solution under Open Source terms: Opencow: Open Layer for Unicode

Overall, there are 2 Open Source alternatives available:

1) libunicows (http://libunicows.sourceforge.net/) — provides an  
MIT-licensed version of only the UNICOWS.LIB link-library. Still requires  
the Microsoft-provided UNICOWS.DLL or the Mozilla OPENCOW.DLL, but has no  
redistribution restrictions (since no Microsoft code redistributed)

2) opencow (previously MZLU) (http://opencow.sourceforge.net/) —  
reimplements both the DLL and LIB link-library as MPL 1.1/GPL 2.0/LGPL  
2.1, originally for the Mozilla project