[El Capitan beta 2] brew update error: unable to unlink old 'README.md' (Permission denied)

[simonwhitaker]

$ brew update
error: unable to unlink old 'README.md' (Permission denied)
Error: Failure while executing: git pull -q origin refs/heads/master:refs/remotes/origin/master
$ brew --version
0.9.5

[DomT4]

What does ls -lh $(brew --prefix) say?

[lloeki]

My bet is on ls -ld $(brew --prefix), which will probably show it's owned by root instead of the user (unlinking is a directory operation).

[simonwhitaker]

Correct, it showed /usr/local/ owned by root. That appears to have changed on installing 10.11 beta 2, I'm pretty sure I used brew without issue on beta 1.

(To be clear, I'm not suggesting this is a bug in Homebrew, just giving you a heads-up in case it turns out to be a systemic issue with 10.11 rather than a glitch in the latest beta.)

[lloeki]

This is systemic, as the OS X installer does it. Yosemite did that too. Also, brew doctorpoints it out.

[DomT4]

Strange. I updated my VM from 10.11 DP1 to DP2 the other night and haven't had any issues with /usr/local being reclaimed. Can you sudo chown -R it back to you?

[GuamBomb]

Could have something to do with "rootless," the new security feature. I keep finding little things broken by it. To disable it, you can use the command <sudo nvram boot-args="rootless=0"> and then reboot. To turn it back on, you change that 0 to a 1 and reboot again.

[DomT4]

We're trying to work with rootless, rather than around it.

For better or worse we have to assume users will have rootless enabled and them doing so actually should reduce the amount of Issues Homebrew fields when people do things like symlinking Homebrew's LLVM over the system one, removing the Python in /usr/bin, changing plists in /System and so on.

/usr/local is supposed to be available to developers under rootless, per Apple's announcement.

[DomT4]

Moving to tracking in #40837.