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 Ways that CSS and JavaScript Interact That You May Not Know About

    CSS and JavaScript:  the lines seemingly get blurred by each browser release.  They have always done a very different job but in the end they are both front-end technologies so they need do need to work closely.  We have our .js files and our .css, but...

Incredible Demos

  • By
    MooTools: Set Style Per Media

    I'd bet one of the most used MooTools methods is the setStyle() method, which allows you to set CSS style declarations for an element. One of the limitations of MooTools' setStyle() method is that it sets the specific style for all medias.

  • By
    Check All/None Checkboxes Using MooTools

    There's nothing worse than having to click every checkbox in a list. Why not allow users to click one item and every checkbox becomes checked? Here's how to do just that with MooTools 1.2. The XHTML Note the image with the ucuc ID -- that...

Discussion

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