# Mass batch processing on the CLI 2022-03-19 00:00 > This post is day 4 of me taking part in the > #100DaysToOffload challenge. => https://100daystooffload.com/ #100DaysToOffload Some time ago, I needed to process a lot of video files with vlc. This is usually pretty easy to do, `for file in *.mp4 ; do ffmpeg ... ; done` is about all you need in most cases. However, sometimes the files you are trying to process are in different folders. And sometimes you want to process some files in a folder but not others. That's the exact situation I was in, and I was wondering if I needed to find some graphical application with batch processing capabilities so I can queue up all the processing I need. After a bit of thinking though, I realized I could do this very easily with a simple shell script! That shell script lives in my mark-list repository. => https://github.com/SeriousBug/mark-list mark-list The idea is simple, you use the command to mark a bunch of files. Every file you mark is saved into a file for later use. ```bash $ mark-list my-video.mp4 # Choose a file Marked 1 file. $ mark-list *.webm # Choose many files Marked 3 files. $ cd Downloadsr $ mark-list last.mpg # You can go to other directories and keep marking ``` You can mark a single file, or a bunch of files, or even navigate to other directories and mark files there. Once you are done marking, you can recall what you marked with the same tool: ```bash $ mark-list --list /home/kaan/my-video.mp4 /home/kaan/part-1.webm /home/kaan/part-2.webm /home/kaan/part-3.webm /home/kaan/Downloads/last.mpg ``` You can then use this in the command line. For example, I was trying to convert everything to `mkv` files. ```bash for file in `mark-list --list` ; do ffmpeg -i "${file}" "${file}.mkv" ; done ``` It works! After you are done with it, you then need to clear out your marks: ``` mark-list --clear ``` Hopefully this will be useful for someone else as well. It does make it a lot easier to just queue up a lot of videos, and convert all of them overnight.