Where does brew set $PATH on OSX (mac)?

[mecoookie]

Output of brew config

HOMEBREW_VERSION: 4.0.15
ORIGIN: https://github.com/Homebrew/brew
HEAD: 763c41f006ab9b44261e313b0aaa24a047431b06
Last commit: 15 hours ago
Core tap origin: https://github.com/Homebrew/homebrew-core
Core tap HEAD: 7ee397e828fc2b17eff92e614a8a0d2e5417419c
Core tap last commit: 2 hours ago
Core tap branch: master
Core tap JSON: 24 Apr 22:37 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_MAKE_JOBS: 10
Homebrew Ruby: 2.6.10 => /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby
CPU: 10-core 64-bit arm_firestorm_icestorm
Clang: 14.0.3 build 1403
Git: 2.39.2 => /Applications/Xcode.app/Contents/Developer/usr/bin/git
Curl: 7.86.0 => /usr/bin/curl
macOS: 13.2.1-arm64
CLT: N/A
Xcode: 14.3
Rosetta 2: false

Output of brew doctor

Your system is ready to brew.

Description of issue

Where does brew modify the $PATH on OSX (Mac)?

This is the output of my path directory:

% echo $PATH
/Users/josh/opt/anaconda3/bin:/Users/josh/opt/anaconda3/condabin:/usr/local/opt/python/libexec/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Applications/Little Snitch.app/Contents/Components:/Library/Apple/usr/bin

I have brew installed with conda, and I'm finding conda puts it's paths in the front head of homebrew, but I can't find where brew actually sets it's path variables!

I checked my .zshrc, .bash_profile, /etc/paths, and /etc/paths.d.
I can't find anywhere that the Brew directories are adde to $PATH. Is it a new setting in the system somewhere? or a file I don't know?

I want to make sure brew commands are taking preference, at least during testing, so I'd like to set my path so the brew directories come first.

[carlocab]

You probably have an

eval "$(/opt/homebrew/bin/brew shellenv)"

somewhere in your config files that does this.

[cho-m]

If you copy-pasted output of Homebrew installer, then it will be in:

• .zprofile for ZSH (default on macOS)
• .bash_profile or .profile if you changed shell to Bash
• .profile everywhere else (again if you changed shell to something like csh/tsch/ksh/...)

See: https://github.com/Homebrew/install/blob/master/install.sh#L992-L1005

---

For interactive+login ZSH terminal, your shell will load .zprofile before .zshrc, so that may impact PATH order if prepended in both files.

Other config files also exist that you may want to check.

See: https://zsh.sourceforge.io/Doc/Release/Files.html

[JosephTLyons]

@mecoookie, did you ever find out where brew sets the $PATH? I'm looking everywhere on my end and can't find a single thing setting it - no idea how it is ending up in the $PATH.

[gromgit]

I've answered this question enough times that I decided to write a script for folks to use. brew tap gromgit/brewtils, then brew trace-login to run a complete traced login process that logs to /tmp/trace.log by default.

brew trace-login --help to see the various options available. For instance, brew trace-login -- -w PATH= will print just the lines that set PATH.