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
    5 HTML5 APIs You Didn’t Know Existed

    When you say or read "HTML5", you half expect exotic dancers and unicorns to walk into the room to the tune of "I'm Sexy and I Know It."  Can you blame us though?  We watched the fundamental APIs stagnate for so long that a basic feature...

Incredible Demos

  • By
    Vertically Centering with Flexbox

    Vertically centering sibling child contents is a task we've long needed on the web but has always seemed way more difficult than it should be.  We initially used tables to accomplish the task, then moved on to CSS and JavaScript tricks because table layout was horribly...

  • By
    WebKit-Specific Style:  -webkit-appearance

    I was recently scoping out the horrid source code of the Google homepage when I noticed the "Google Search" and "I'm Feeling Lucky" buttons had a style definition I hadn't seen before:  -webkit-appearance.  The value assigned to the style was "push-button."  They are buttons so that...

Discussion

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