How to Set Date Time from Mac Command Line

By  on  

Working on a web extension that ships to an app store and isn't immediately modifiable, like a website, can be difficult. Since you cannot immediately deploy updates, you sometimes need to bake in hardcoded date-based logic. Testing future dates can be difficult if you don't know how to quickly change the date on your local machine.

To change the current date on your Mac, execute the following from command line:

# Date Format:  MMDDYYYY
sudo date -I 06142024

This command does not modify time, only the current date. Using the same command to reset to current date is easy as well!

Recent Features

  • By
    5 Awesome New Mozilla Technologies You’ve Never Heard Of

    My trip to Mozilla Summit 2013 was incredible.  I've spent so much time focusing on my project that I had lost sight of all of the great work Mozillians were putting out.  MozSummit provided the perfect reminder of how brilliant my colleagues are and how much...

  • 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
    Create a Quick MooTools Slideshow with Preloading Images

    I've been creating a lot of slideshow posts lately. Why, you ask? Because they help me get chicks. A quick formula for you: The following code snippet will show you how to create a simple slideshow with MooTools; the script will also...

  • By
    Create Keyboard Shortcuts with Mousetrap

    Some of the finest parts of web apps are hidden in the little things.  These "small details" can often add up to big, big gains.  One of those small gains can be found in keyboard shortcuts.  Awesome web apps like Gmail and GitHub use loads of...

Discussion

  1. Richard

    I didn’t understand your exact use case, but a helpful way to do date-related testing without modifying your actual computer date/time, is to shim the system calls with library pre-loading. On a Mac, dyld can do this with DYLD_LIBRARY_PATH. On Linux, GNU ld can do it with LD_LIBRARY_PATH.

    This makes it easy to write tests for specific situations, such as monthly changeovers, leap-occurrences, timezones, etc.

    “libfaketime” is a handy library written for this, https://github.com/wolfcw/libfaketime. It’s even packaged in homebrew, just do brew install libfaketime. :)

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