无法在 Mac (El-Capitan) 上创建文件夹,权限错误

Unable to create folder on Mac (El-Capitan), permission error

这个简单的错误让我很困惑:

(0)root@vpn-client-228# mkdir ruby-2.0.0-p645
mkdir: ruby-2.0.0-p645: Operation not permitted
(1)root@vpn-client-228# pwd
/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/include/ruby-2.0.0
(0)root@vpn-client-228# 

这是我能想到的所有调试信息:

(0)root@vpn-client-228# dd='/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/include/ruby-2.0.0/ruby-2.0.0-p645'
(0)root@vpn-client-228# while [ "`dirname $dd`" != "/" ]; do dd=`dirname $dd`; ls -ld $dd; done
drwxr-xr-x  5 root  wheel  170 Dec  9 10:55 /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/include/ruby-2.0.0
drwxr-xr-x  3 root  wheel  102 Aug 22 19:06 /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/include
drwxr-xr-x  6 root  wheel  204 Nov 24 11:19 /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr
drwxr-xr-x  7 root  wheel  238 Dec 14 09:52 /System/Library/Frameworks/Ruby.framework/Versions/2.0
drwxr-xr-x  4 root  wheel  136 Sep 17 07:27 /System/Library/Frameworks/Ruby.framework/Versions
drwxr-xr-x  6 root  wheel  204 Dec  9 10:55 /System/Library/Frameworks/Ruby.framework
drwxr-xr-x  135 root  wheel  4590 Dec  9 10:55 /System/Library/Frameworks
drwxr-xr-x  79 root  wheel  2686 Nov 24 15:40 /System/Library
drwxr-xr-x@ 4 root  wheel  136 Dec 14 09:53 /System
(0)root@vpn-client-228# 
(0)root@vpn-client-228# 
(0)root@vpn-client-228# uname -a
Darwin vpn-client-228.sv2 15.2.0 Darwin Kernel Version 15.2.0: Fri Nov 13 19:56:56 PST 2015; root:xnu-3248.20.55~2/RELEASE_X86_64 x86_64
(0)root@vpn-client-228# 
(0)root@vpn-client-228# 
(0)root@vpn-client-228# id
uid=0(root) gid=0(wheel) groups=0(wheel),1(daemon),2(kmem),3(sys),4(tty),5(operator),8(procview),9(procmod),12(everyone),20(staff),29(certusers),61(localaccounts),80(admin),701(com.apple.sharepoint.group.1),702(com.apple.sharepoint.group.2),33(_appstore),98(_lpadmin),100(_lpoperator),204(_developer),395(com.apple.access_ftp),398(com.apple.access_screensharing),399(com.apple.access_ssh)
(0)root@vpn-client-228#

上下文是我正在尝试安装 perftools (sudo gem install perftools.rb -v '2.0.0'),它因错误 /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/fileutils.rb:245:in 'mkdir': Operation not permitted - /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/include/ruby-2.0.0/ruby-2.0.0-p645 (Errno::EPERM)' 而失败,我正在尝试调试它。

不要以 Root 身份安装 Gem

没有。只是 "No." 不要 曾经 以 root 身份安装 gems。除非你必须真正知道自己在做什么,并且愿意在你搞砸的时候重新安装 OS。所以别这样。

如何做对

始终使用 Ruby 版本管理器,例如 rvm, rbenv, or chruby。即使在生产机器上,这也会让你省去很多麻烦。

特别是,El Capitan 有一个新的 System Integrity Protection (SIP) 系统,该系统依赖于应用于重要路径和应用程序的特殊标志。 Ruby 是那些二进制文件之一:

$ ls -lO /usr/bin/ruby 
-r-xr-xr-x  1 root  wheel  restricted,compressed 42928 Oct 17 19:47 /usr/bin/ruby

虽然我不敢发誓,但 RubyGems 试图修改的文件或目录可能也受到保护。虽然您 可以 绕过 SIP,但这样做是一个非常糟糕的主意™。相反,您应该使用版本管理器之一(Homebrew 中包含 rbenv 和 chruby)来安装非系统 rubies 和管理 gems。