Get File MIME Type from Command Line
I've gotten skilled at shell scripting over the years. I love a good GUI but knowing how to automate makes you a much more powerful engineer. Much of my scripting requires recursing over directories and processing a file if it meets a given criteria, which is often file extension or MIME type.
You can use the following shell command to get a file's MIME type:
file --mime-type -b Downloads/main.js
# text/plain
file --mime-type -b Downloads/logo.jpg
# image/jpeg
It's important to use the brief (-b) option in the command or you may receive an error message.
MIME type is used for validation and any number of other informational use cases. Luckily the file command and and a flag is all you need!
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