初めて PostgreSQL データベースに基づいて RoR アプリをインストールし、コマンドrails new psql_app -d postgresqlを実行した後、次の問題が発生します。
...
create vendor/assets/javascripts/.gitkeep
create vendor/assets/stylesheets
create vendor/assets/stylesheets/.gitkeep
create vendor/plugins
create vendor/plugins/.gitkeep
run bundle install
/Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:243:in `mkdir': Permission denied - /Users/adam/.gem/specs/rubygems.org%443 (Errno::EACCES)
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:243:in `fu_mkdir'
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:217:in `block (2 levels) in mkdir_p'
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:215:in `reverse_each'
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:215:in `block in mkdir_p'
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:201:in `each'
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/fileutils.rb:201:in `mkdir_p'
from /Users/adam/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/site_ruby/1.9.1/rubygems/spec_fetcher.rb:125:in `fetch_spec'
from /Users/adam/.rvm/gems/ruby-1.9.2-p290@global/gems/bundler-1.0.21/lib/bundler/remote_specification.rb:47:in `_remote_specification'
from /Users/adam/.rvm/gems/ruby-1.9.2-p290@global/gems/bundler-1.0.21/lib/bundler/remote_specification.rb:53:in `method_missing'
from /Users/adam/.rvm/gems/ruby-1.9.2-p290@global/gems/bundler-1.0.21/lib/bundler/resolver.rb:101:in `block in __dependencies'
....
また、PostgreSQL データベースへの接続を再設定しようとしましたが、成功しませんでした...それでもこのエラーが発生します。MySQL データベースで新しいアプリを作成しようとすると、このエラーが発生しません。