I have hundreds of files in various different subdirectories. Some of them have the correct file extension, but some of them don't. I want to rename all files that don't have a file extension and append a .mp4 extension to their file name. The other files should be left untouched. How can I automate this renaming operation using Bash? Or do I need a real scripting language like Perl or Python for this?
Add file extension to files that have no extension
bash;files;rename
Something like this:find . -type f  ! -name *.* -exec mv {} {}.mp4 \;