C:\Nginx\html\riv-sa.com>gem install unicorn
Fetching: kgio-2.9.2.gem (100%)
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing unicorn:
        ERROR: Failed to build gem native extension.

    C:/Ruby200/bin/ruby.exe extconf.rb
checking for CLOCK_MONOTONIC in time.h... yes
checking for clockid_t in time.h... yes
checking for clock_gettime() in -lrt... no
checking for t_open() in -lnsl... no
checking for socket() in -lsocket... no
checking for poll() in poll.h... no
checking for getaddrinfo() in sys/types.h,sys/socket.h,netdb.h... no
getaddrinfo required
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers.  Check the mkmf.log file for more details.  You may need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/Ruby200/bin/ruby
        --with-rtlib
        --without-rtlib
        --with-nsllib
        --without-nsllib
        --with-socketlib
        --without-socketlib


Gem files will remain installed in C:/Ruby200/lib/ruby/gems/2.0.0/gems/kgio-2.9.2 for inspection.
Results logged to C:/Ruby200/lib/ruby/gems/2.0.0/gems/kgio-2.9.2/ext/kgio/gem_make.out