Automatically modify $PATH with /etc/paths.d

[szhu]

MacTeX and some other software packages install binaries to non-standard locations. This necessitates caveats like the one added by #2284:

==> Caveats
To use mactex, you may need to add the /usr/texbin directory
to your PATH environment variable, eg (for bash shell):

  export PATH=/usr/texbin:"$PATH"

There's actually a really elegant solution to appending to $PATH on OS X: Just add a file with the path to append in /etc/paths.d. When shells start, they run path_helper, which parses /etc/path and the files in /etc/paths.d to construct the correct $PATH. Such a "path file" would be easy for Homebrew to install and uninstall. Or, alternatively, a Cask "path file" could be installed that would contain all the paths of the currently installed formulae.

Not only does this solution automate something that users would need to do by hand, but also it is, unlike the solution recommended by the caveat note, both auto-uninstallable and shell-agnostic.

[rolandwalker]

+1 for adding the capability within homebrew-cask.

For this specific package -- I believe that MacTeX already does create a file under /etc/paths.d.

[szhu]

If MacTeX already creates the file, then why is the caveat needed?

[rolandwalker]

Excellent question! We need to check closer.

This is a particularly slow one to install/uninstall, so I'm sure it will be at least a few days before we come around to testing it.

[szhu]

Haha, I've been trying to install it for a few days and I still haven't managed to download it intact.

[szhu]

On a related note, any particular reason this download is so slow? Are there any faster mirrors available?

[szhu]

Finally installed. It looks like MacTeX installs /etc/paths.d/TeX, making the caveat unnecessary. If someone can confirm this, I can submit a PR.

Related questions:

1. Homebrew wants /usr/local/sbin to be in $PATH. Would it be a good idea to add it to paths.d if brew --prefix is /usr/local?
2. XQuartz installs the file /etc/paths.d/40-XQuartz. Is there a purpose for the 40 that needs to be taken into consideration should paths.d-modification be built into Cask or Homebrew?

[rolandwalker]

Your research on this is greatly appreciated!

Now it is me waiting for the download. I've never found a really fast CTAN mirror either.

The 40 in the filename is an old-fashioned hack to control the order in which the path elements are added. Files are traditionally named by tens on the theory that you might need the ones place later to insert something between.

As to the Homebrew path, we try not to step on each others' toes. That setting would seem to make sense for users to do, or for Homebrew to do, but it shouldn't be part of this project.

[joethorley]

Finally installed. It looks like MacTeX installs /etc/paths.d/TeX, making the caveat unnecessary. If
someone can confirm this, I can submit a PR.

I can confirm that running the following code

brew tap phinze/cask
brew install brew-cask
brew cask install mactex

installs /etc/paths.d/TeX

with the contents

/usr/texbin

I can also confirm that brew cask install mactex took hours and required several attempts (which continued from where the previous attempt left off)

[goxberry]

@rolandwalker I added the caveat to BasicTeX in #2311. The reason the caveat was added in the first place due to Homebrew/legacy-homebrew#25719; it affects zsh users, because a default Homebrew zsh configuration doesn't necessarily import paths from /etc/paths.d. The caveat is unnecessary for bash and fish users.

[alebcay]

It seems this was addressed in v0.32.0 (pull request #3699). Should this be closed?

[szhu]

It's not completely addressed. From #3685 comment 38804186:

The original idea in #3597 was that we add the ability to manipulate the contents of /etc/paths.d. That still seems worth doing.

[rolandwalker]

Yes, please keep this open as I am assigned and intend to implement.

[szhu]

Heads-up, BasicTex doesn't seem to install anything to /etc/paths.d like MacTex does (but I think it should, as otherwise some programs can't locate the installed commands).

For reference: basictex.rb • mactex.rb

[rolandwalker]

Thanks. Then that's the perfect use-case for this proposed feature.

[vitorgalvao]

Closing for lack of interest/implementation. This is definitely non-urgent, and can be revisited later.