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meu env:
play@ubuntu:~$ gem env
RubyGems Environment:
- RUBYGEMS VERSION: 1.8.24
- RUBY VERSION: 1.9.3 (2012-11-10 patchlevel 327) [x86_64-linux]
- INSTALLATION DIRECTORY: /home/play/.rvm/gems/ruby-1.9.3-p327-dev
- RUBY EXECUTABLE: /home/play/.rvm/rubies/ruby-1.9.3-p327-dev/bin/ruby
- EXECUTABLE DIRECTORY: /home/play/.rvm/gems/ruby-1.9.3-p327-dev/bin
- RUBYGEMS PLATFORMS:
- ruby
- x86_64-linux
- GEM PATHS:
- /home/play/.rvm/gems/ruby-1.9.3-p327-dev
- /home/play/.rvm/gems/ruby-1.9.3-p327-dev@global
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :benchmark => false
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- http://rubygems.org/
ao tentar instalar o libnotify:
play@ubuntu:~$ sudo gem install ruby-libnotify
Building native extensions. This could take a while...
ERROR: Error installing ruby-libnotify:
ERROR: Failed to build gem native extension.
/usr/bin/ruby1.9.1 extconf.rb
/usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in 'require': cannot load such file -- mkmf (LoadError)
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in 'require'
from /usr/lib/ruby/vendor_ruby/mkmf-gnome2.rb:13:in '<top (required)>'
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in 'require'
from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in 'require'
from extconf.rb:11:in '<main>'
Gem files will remain installed in /var/lib/gems/1.9.1/gems/ruby-libnotify-0.5.1 for inspection.
Results logged to /var/lib/gems/1.9.1/gems/ruby-libnotify-0.5.1/ext/gem_make.out
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