in reply to Directory operations and Unicode

How would someone use Window's UTF16LE unicode aware APIs with Perl's ASCII until infected with UTF8 string system in XS? I looked for examples of MultiByteToWideChar in perl's source.
1. in win32/win32.c#l815 in perl.git and https://metacpan.org/source/COSIMO/Win32-API-0.60/API.xs#L139 MultiByteToWideChar was set up with "CP_ACP ANSI code page" always.
2. In cpan/Win32/Win32.xs#l161 in perl.git, the SV is checked for utf8 flag, if so its converted as CP_UTF8, otherwise, CP_ACP.
3. or better to force all SVs to utf8 using perl api before MultiByteToWideChar then with CP_UTF8 like in https://metacpan.org/source/BJOERN/Win32-MultiLanguage-0.72/MultiLanguage.xs#L51?
4. Or is it best to leave is to the caller to UTF16LE encode their scalars using Encode and pass "binary garbage" scalars to XS, then nothing but a SvPV, and cast the PV */char * to a wchar_t * the way its done in Win32API::File?
5. use mbstowcs instead of MultiByteToWideChar? mbstowcs uses null string end marking, not exactly safe
6. so far all examples of MultiByteToWideChar, the flags parameter has been zero, except for https://metacpan.org/source/SOMMAR/Win32-SqlServer-2.007/convenience.cpp#L51, where its MB_PRECOMPOSED for ascii and 0 for utf8. Whats the correct handling for the flags parameter of MultiByteToWideChar?

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Re^2: Directory operations and Unicode
by Anonymous Monk on Nov 06, 2011 at 05:18 UTC
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Re^2: Directory operations and Unicode
by nikosv (Deacon) on Nov 06, 2011 at 05:21 UTC
    When using Win32::COM I subsequently use the OS COM facilities, hence I bypass any Wide APIs, call the Scripting.FileSystemObject and access the filesystem in UTF: 
    Win32::OLE->Option(CP => Win32::OLE::CP_UTF8);
$obj = Win32::OLE->new('Scripting.FileSystemObject');

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    and manipulate its methods, for example : 
    $folder = $obj->GetFolder(".");
$collection= $folder->{Files};

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    If you want to keep your sanity do not start looking into the wide API's ! :)
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[d/l]
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      When using Win32::COM I subsequently use the OS COM facilities, hence I bypass any Wide APIs, call the Scripting.FileSystemObject and access the filesystem in UTF

      No. You don't bypass the Wide APIs, you wrap them using a ridiculously large stack of other APIs. After uselessly burning a lot of CPU cycles, the Scripting.FileSystemObject finally ends calling the Wide APIs.

      Alexander

      --
      Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)
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        hence I bypass any Wide APIs

        in the sense that I don't have to deal or think about them them

        you wrap them using a ridiculously large stack of other APIs. After uselessly burning a lot of CPU cycles

        might be true but it gets the job done. what is your suggestion of doing it otherwise ?

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