It’s very simple to rename the files to lowercase/uppercase using awk:

Lowercase
[cc lang=”bash”]
ls -1rt | awk ‘{ printf(“mv %s %s\n”, $0, tolower($0)) | “sh” } END { close(“sh”) }’
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Uppercase
[cc lang=”bash”]
ls -1rt | awk ‘{ printf(“mv %s %s\n”, $0, toupper($0)) | “sh” } END { close(“sh”) }’
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