Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
	ERROR: Failed to build gem native extension.

        /home/pbrunet/.rbenv/versions/1.9.3-p194/bin/ruby extconf.rb
checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for mysql.h... no
checking for mysql/mysql.h... yes
checking for errmsg.h... no
-----
errmsg.h is missing.  please check your installation of mysql and try again.
-----
*** 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=/home/pbrunet/.rbenv/versions/1.9.3-p194/bin/ruby
	--with-mysql-config
	--without-mysql-config


Gem files will remain installed in /home/pbrunet/.rbenv/versions/1.9.3-p194/lib/ruby/gems/1.9.1/gems/mysql2-0.3.11 for inspection.
Results logged to /home/pbrunet/.rbenv/versions/1.9.3-p194/lib/ruby/gems/1.9.1/gems/mysql2-0.3.11/ext/mysql2/gem_make.out