Re: Filenames in Ada

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Wed, 23 Nov 2005 18:36:47 +0100, Martin Krischik wrote:

> However, filenames in music collections contain all sort of funny characters 
> (especially the my wife's music - allmost entirely in Cyrillic) - no big
> deal for modern file systems. But a big deal for Ada as it seams. Not only
> are all filenames in Ada.Directories of type String - actually all
> filenames anywhere are just String.
> 
> How does one deal with modern (utf-8) filenames in Ada?

An interesting question! Indeed the file name parameter is of String type.

Well, some quick check. The following works fine under Fedora / GNAT:

with Ada.Text_IO;                 use Ada.Text_IO;
with Strings_Edit.UTF8.Handling;  use Strings_Edit.UTF8.Handling;

procedure UTF8_Test is
   Name : Wide_String :=
          (  Wide_Character'Val (1092)
          &  Wide_Character'Val (1072)
          &  Wide_Character'Val (1081)
          &  Wide_Character'Val (1083)
          );
   File : File_Type;
begin
   Create (File, Out_File, To_UTF8 (Name));
   Close (File);
end UTF8_Test;

If you have Cyrillic code page installed you will see the file name
correctly spelt in Russian. No wonder, Fedora Linux is natively UTF-8!

Though it cannot work under Windows, because GNAT run-time translates
Create into some CreateFileA Windows API. Moreover Windows is UTF-16. So
there is no chance for Ada.Text_IO.Create. I presume one could directly use
CreateFileW from Windows API with a Wide_String file name, but that's
another story.

> Is there a chance for an add-on package (to late for Ada 2005) or are we
> snookered until Ada 2015.

I don't see any great problem here. I would add UTF-8 variants for all
calls where a file name is mentioned. We could even switch from Latin-1 to
UTF-8. This seems to be independent on Text_IO vs. Wide_Text_IO issue.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de