Get File MIME Type from Command Line

By  on  

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!

Recent Features

  • By
    JavaScript Promise API

    While synchronous code is easier to follow and debug, async is generally better for performance and flexibility. Why "hold up the show" when you can trigger numerous requests at once and then handle them when each is ready?  Promises are becoming a big part of the JavaScript world...

  • By
    CSS @supports

    Feature detection via JavaScript is a client side best practice and for all the right reasons, but unfortunately that same functionality hasn't been available within CSS.  What we end up doing is repeating the same properties multiple times with each browser prefix.  Yuck.  Another thing we...

Incredible Demos

  • By
    MooTools Window Object Dumping

    Ever want to see all of the information stored within the window property of your browser? Here's your chance. The XHTML We need a wrapper DIV that we'll consider a console. The CSS I like making this look like a command-line console. The MooTools JavaScript Depending on what you have loaded...

  • By
    Dynamic Waveform Visualizations with wavesurfer.js

    Waveform images are an awesome addition to boring audio widgets.  They can be functional as well as aesthetically pleasing, allowing users to navigate audio visually.  I recently found wavesurfer.js, an amazing waveform image utility that uses to Web Audio API to create super customizable...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!