Ruby on Rails

Hello @colin when i tried to ru gem install nokogiri -v '1.6.6.2' -- --use-system-libraries --with-xml2-include=/usr/include/libxml2 --with-xml2-lib=/usr/lib
 command with out using Sudo i got this  message-Error installing nokogiri:
    ERROR: Failed to build gem native extension. Its kind of error that extconf.rb
so after that i tried gem install rails but the same error.
If Any mistake made by me then please help me to correct on this.

if i use sudo gem install rails, its showing 31 gems already installed,but when i type rails -v it showing me

/usr/lib/ruby/1.9.1/rubygems/dependency.rb:247:in `to_specs': Could not find railties (>= 0) amongst [activesupport-4.2.4, bundler-1.10.6, bundler-unload-1.0.2, executable-hooks-1.3.2, gem-wrappers-1.2.7, i18n-0.7.0, mini_portile-0.6.2, minitest-5.8.0, rails-deprecated_sanitizer-1.0.3, rubygems-bundler-1.4.4, rvm-1.11.3.9, thread_safe-0.3.5, tzinfo-1.2.2] (Gem::LoadError)
    from /usr/lib/ruby/1.9.1/rubygems/dependency.rb:256:in `to_spec'
    from /usr/lib/ruby/1.9.1/rubygems.rb:1231:in `gem'
    from /usr/local/bin/rails:22:in `<main>'


so i please help me to get over this..


On Monday, September 14, 2015 at 3:34:22 PM UTC+5:30, Prasanna Moharana wrote:

Hello every body am very new to this group.
i have some issue regarding Rails installation.Though i have installed Ruby,bundler etc i was trying to install rails using gem install rails command but there are some error like

ERROR:  Error installing rails:
    ERROR: Failed to build gem native extension.

    /home/prasanna/.rvm/rubies/ruby-2.2.3/bin/ruby -r ./siteconf20150914-3856-mtv6bq.rb extconf.rb
checking if the C compiler accepts ... *** 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/prasanna/.rvm/rubies/ruby-2.2.3/bin/$(RUBY_BASE_NAME)
    --help
    --clean


so can any body please help me to tackle this..

PS.Tried -sudo apt-get install mkmf ,
gem install mkmf
build essential command etc..so please help me to get rid of these..