Non-ASCII characters in filenames/Unicode

[John Collins]

I am updating latexmk so that it more correctly handles non-ASCII characters in 
filenames.  Particular problems are caused by the difference between the UTF-8 
encoding used in .log, .fls, and .aux files etc, and the typically non-UTF-8 
system code page used in Windows.  I have two questions for the TL maintainers 
(and anyone else interested):

1. Where do I look for how these things are done in the TL programs, especially 
any that are written in Perl?  Who should I ask about this?

2. On a Windows system where the **system** code page is not 65001, the PWD 
line at the top of an fls file is encoded in in the system code page.  The rest 
of the file is encoded in UTF-8.  Is this a bug?

Thanks,
John Collins