Your example shows a very particular shortcoming in the unix command line programs. The mv command doesn't play nice with spaces in file names. I think python

Your example shows a very particular shortcoming in the unix command line programs. The mv command doesn't play nice with spaces in file names. I think python is a fine solution for your use case and wouldn't recommend against your code. Especially if you had to build it out for a lot of different patterns. But if you're dealing with changing stuff in text files greater than 25 gigs I'd always recommend using the unix cmd line tool set for simple modifications if performance is a key concern. It works the same everywhere and can rip through big files. But I'm a Vim guy and I live in the shell so I'm surely quite biased lol. There are plenty of pretty easy one liners though that can rename files depending on if you can define a pattern correctly though. echo 'TV Show Name 2014.L337.H4XXX1080p-420.mkv' | awk -F . -v q="'" '{print q$0q" "q$1".mkv"q }' | xargs mv find . -type f -name '*.mkv' -printf '%f' | awk -F . -v q="'" '{print q$0q" "q$1".mkv"q}' | xargs mv