rbenv/foreman Permission denied @ rb_sysopen - /etc/init/app.conf (Errno::EACCES)

Someone knows how to give rbenv permission to rbenv/foreman export? thank's

[foreman export] writing: app.conf /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/lib/foreman/export/base.rb:162:in initialize': Permission denied @ rb_sysopen - /etc/init/app.conf (Errno::EACCES) from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/lib/foreman/export/base.rb:162:inopen' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/lib/foreman/export/base.rb:162:in write_file' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/lib/foreman/export/base.rb:139:inwrite_template' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/lib/foreman/export/upstart.rb:12:in export' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/lib/foreman/cli.rb:61:inexport' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/command.rb:27:in run' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/invocation.rb:126:ininvoke_command' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor.rb:359:in dispatch' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/thor-0.19.1/lib/thor/base.rb:440:instart' from /home/ubuntu/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/foreman-0.82.0/bin/foreman:7:in <top (required)>' from /home/ubuntu/.rbenv/versions/2.2.2/bin/foreman:23:inload' from /home/ubuntu/.rbenv/versions/2.2.2/bin/foreman:23:in `'