If you try to install the nokogiri gem on freebsd you may get the following error message:
libiconv is missing. please visit http://nokogiri.org/tutorials/installing_nokogiri.html for help with installing dependencies.
In that case it should suffice to use the following command to install the gem:
% gem install nokogiri -v 'DESIRED_VERSION' -- --with-iconv-lib=/usr/local/lib --with-iconv-include=/usr/local/include
If you get further error messages complaining about libxslt or libxml you may need a couple more options:
% gem install nokogiri -v 'DESIRED_VERSION' -- --use-system-libraries \ --with-iconv-lib=/usr/local/lib --with-iconv-include=/usr/local/include \ --with-xml2-lib=/usr/local/lib --with-xml2-include=/usr/local/include/libxml2/libxml \ --with-xslt-lib=/usr/local/lib --with-xslt-include=/usr/local/include/libxslt