From: "afazio (Alfred Fazio)" Date: 2013-02-22T00:17:58+09:00 Subject: [ruby-core:52627] [Backport 200 - Backport #7886] Not recognizing unix group permissions for Mac OS X (Mountain Lion) when user account have >16 groups Issue #7886 has been updated by afazio (Alfred Fazio). Thank you!! ---------------------------------------- Backport #7886: Not recognizing unix group permissions for Mac OS X (Mountain Lion) when user account have >16 groups https://bugs.ruby-lang.org/issues/7886#change-36714 Author: afazio (Alfred Fazio) Status: Assigned Priority: Normal Assignee: nagachika (Tomoyuki Chikanaga) Category: Target version: The following bug occurs in 1.9.3 p374 and also in 1.8.7 p371 When using a Active Directory mobile account in Mac OS X (only tested thus far with Mountain Lion), Ruby does not honor Unix group membership when testing file permissions. Let me give an example: % whoami afazio # I am in the "rvm" group: % groups rvm # Let's create a simple file: % touch test-file % sudo chown root:rvm test-file % sudo chmod 660 test-file % ls -l test-file -rw-rw---- 1 root rvm 4 Feb 19 11:43 test-file # At this moment only root and members of "rvm" group can modify test-file # OS recognizes I have correct permissions: % echo "test data" >> test-file % cat test-file test data # However, Ruby does not: % irb 1.9.3-p374 :001 > File.exists?("test-file") => true 1.9.3-p374 :002 > File.writable?("test-file") => false # To further illustrate, I **can** write to this file in Ruby: pry(main)> File.open("test-file", "w") do |f| pry(main)* f.write("wee") pry(main)* end 3 pry(main)> quit % cat test-file wee -- http://bugs.ruby-lang.org/