Might you consider adding a few lines of code to recognize when the only change in a file is the capitalization of the filename? I know it's a pretty obscure thing (not for me though!), but I imagine it would be easy to implement and test, and it wouldn't slow the program by a measurable amount. Then rather than having to delete the file and copy it again, it could just change the capitalization of the target to match that of the source.
(I often change only the capitalization of my MP3 files' names.)
(I often change only the capitalization of my MP3 files' names.)
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