Set system-wide PATH environment variable for Mac OS GUI apps

This particular problem got me struggled for a while. The first app I installed and wasn’t aware of all my binaries was Emacs.

For some reason it was aware of everything in /usr/bin but not /usr/local/bin. For quite a while I thought it was something related to Emacs.

Then I installed Qute Browser and once again, some binaries available on my system were not in the path when searched from within Qute.

I did some research but didn’t find anything useful. At some point I figured out that if I was starting the GUI app (whether it was Emacs, Qute Browser, MacVim, …) from the terminal, everything was ok. All the binaries on my system could be found.

It got me curious. Why such a different behavior when I launched the app by clicking its icon in the Applications folder or by using Spotlight compared to when I launched it using my term?

Oh boy, this one was a very long road to the true knowledge, the real mastering of Mac OS internals!

The first step to this full understanding was asking myself why my GUI apps would know about the PATH environment variable I set in my shell? It could be set in ~.profile, ~/.bashrc, ~/.bash_profile, ~/.zsh_profile, ~/.zshrc, ~/.config/fish/config.fish, you named it.

It doesn’t makes any sense unless if you start the app from the shell knowing the full blown PATH.

Being confident thanks to this discover I investigated to understand where the GUI apps got their paths from and after some deep diving I got the answer.

EDIT: 2023-07-25
For recent MacOS systems, the solution got easier.
You only have to edit /etc/paths and add the needed paths in it.
Restart your finder and that's it!

Every single app that is started by clicking its icon or through spotlight gets its PATH from whatever is set by launchd daemon.

Now we know this crucial info there’s one simple step left to customize the PATH GUI apps inherit from. It’s as simple as editing /etc/launchd.conf like so:

setenv PATH /usr/local/bin:/usr/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin

Now rather than scanning for binaries only in /usr/bin and /usr/sbin, GUI apps are going to search for binaries in all these paths: /usr/local/bin /usr/local/sbin /usr/bin /bin /usr/sbin /sbin.

If you want your changes to be effective without having to reboot your computer – I hate rebooting my computer – you’ll have to follow some more steps.

This steps will help launchd and Spotlight to be aware of the new settings:

$ egrep "^setenv\ " /etc/launchd.conf | xargs -t -L 1 launchctl

This one greps all environment related settings and forward them to launchd.

Then you have to restart your Dock and Spotlight apps:

$ killall Dock
$ killall Spotlight

Now every GUI app you launch inherits of this PATH env variable, either you launch it by clicking the icon in Applications folder or using Spotlight!

Enjoy!