title: Trouble installing ruby-oci8 gem
body: <p>I'm trying to install a gem <code>ruby-oci8</code> on the rails. </p>
  
  <p>I get the following error,</p>
  
  <p><strong>$ gem install ruby-oci8</strong></p>
  
  <pre><code>Building native extensions.  This could take a while...
  ERROR:  Error installing ruby-oci8:
          ERROR: Failed to build gem native extension.
  
      current directory: /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8
  /home/solovievga/.rvm/rubies/ruby-2.4.2/bin/ruby -r ./siteconf20180213-21757-1hli0rl.rb extconf.rb
  checking for load library path...
    LD_LIBRARY_PATH is not set.
    checking ld.so.conf... no
  checking for cc... ok
  checking for gcc... yes
  checking for LP64... yes
  checking for sys/types.h... yes
  checking for ruby header... ok
  *** 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/solovievga/.rvm/rubies/ruby-2.4.2/bin/$(RUBY_BASE_NAME)
          --with-instant-client
          --without-instant-client
  /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:909:in `get_home': RuntimeError (RuntimeError)
          from /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:728:in `initialize'
          from /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:269:in `new'
          from /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:269:in `get'
          from extconf.rb:22:in `&lt;main&gt;'
  ---------------------------------------------------
  Error Message:
    Set the environment variable ORACLE_HOME if Oracle Full Client.
    Append the path of Oracle client libraries to LD_LIBRARY_PATH if Oracle Instant Client.
  
  Backtrace:
    /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:909:in `get_home'
    /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:728:in `initialize'
    /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:269:in `new'
    /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1/ext/oci8/oraconf.rb:269:in `get'
    extconf.rb:22:in `&lt;main&gt;'
  ---------------------------------------------------
  See:
   * http://www.rubydoc.info/github/kubo/ruby-oci8/file/docs/install-full-client.md for Oracle full client
   * http://www.rubydoc.info/github/kubo/ruby-oci8/file/docs/install-instant-client.md for Oracle instant client
   * http://www.rubydoc.info/github/kubo/ruby-oci8/file/docs/install-on-osx.md for OS X
   * http://www.rubydoc.info/github/kubo/ruby-oci8/file/docs/report-installation-issue.md to report an issue.
  
  
  To see why this extension failed to compile, please check the mkmf.log which can be found here:
  
    /home/solovievga/.rvm/gems/ruby-2.4.2/extensions/x86_64-linux/2.4.0/ruby-oci8-2.2.5.1/mkmf.log
  
  extconf failed, exit code 1
  
  Gem files will remain installed in /home/solovievga/.rvm/gems/ruby-2.4.2/gems/ruby-oci8-2.2.5.1 for inspection.
  Results logged to /home/solovievga/.rvm/gems/ruby-2.4.2/extensions/x86_64-linux/2.4.0/ruby-oci8-2.2.5.1/gem_make.out
  </code></pre>
  
  <p>I wonder how I can install the ruby-oci8 package?</p>