Case sensitivity

[Alexander Belchenko]

Yep, this problem with Mac is known too. And it also has no solution in bzr yet.
But this problem is rare comparing to case insensitivity on windows.

Michael Haggerty пишет:
> Larry Drews wrote:
>> However, I am running into a problem with filename case sensitivity.  The 
>> filenames from StarTeam are not uniform, their case usage is all over the 
>> map.  I have ended up with two files in the bzr repository that differ only 
>> in case usage.
> 
> Just for fun I'd like to point out that there is another related problem
> that also occurs on *nix systems--that of Unicode normalization.  The
> Subversion project has struggled with this problem, too [1,2].
> 
> I'm not an expert, but here is the problem as I understand it from
> reading the SVN mailing lists:
> 
> Many Unicode characters can be represented in multiple, equivalent ways
> [3].  For example, the precomposed character 'ü' is a canonical
> equivalent to the sequence 'u' and '¨', a combining diaeresis.
> 
> Thus a single "logical" filename, encoded in (say) UTF8, can be
> represented as multiple distinct byte strings.  This is similar to the
> problem that case-insensitive file systems consider some filenames to be
> logically equivalent even though they are represented by different byte
> strings.
> 
> To get around this problem, Unicode defines four "normal forms"; either
> fully composed or fully decomposed, and considering canonical or
> compatible equivalence.  Each unicode string maps to a unique string in
> each of these normal forms, and two strings considered to be equivalent
> map to the same normal forms.
> 
> IIRC, Windows and Linux don't enforce a normal form but typically use
> normal form composed whereas Mac OSX enforces normal-form decomposed.
> This means that the filename used to write a file under Mac OSX is not
> necessarily the same as the filename read back, which caused huge
> problems for Mac OSX users of Subversion.
> 
> So while you are agonizing about case insensitivity, you might also
> consider Unicode normalization :-)
> 
> Michael
> 
> [1] http://trac.macports.org/ticket/17813
> [2]
> http://svn.collab.net/repos/svn/trunk/notes/unicode-composition-for-filenames
> [3] http://en.wikipedia.org/wiki/Unicode_equivalence
> 
> 
>