urujada@gurujada-To-be-filled-by-O-E-M:~$ cd sunil
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ atom .
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ middleman
middleman: command not found
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ middleman
middleman: command not found
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ middleman init
middleman: command not found
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ cd Home
bash: cd: Home: No such file or directory
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ cd..
cd..: command not found
gurujada@gurujada-To-be-filled-by-O-E-M:~/sunil$ cd ..
gurujada@gurujada-To-be-filled-by-O-E-M:~$ cd Home
bash: cd: Home: No such file or directory
gurujada@gurujada-To-be-filled-by-O-E-M:~$ mkdir example
gurujada@gurujada-To-be-filled-by-O-E-M:~$ cd example
gurujada@gurujada-To-be-filled-by-O-E-M:~/example$ middleman init
middleman: command not found
gurujada@gurujada-To-be-filled-by-O-E-M:~/example$ cd ..
gurujada@gurujada-To-be-filled-by-O-E-M:~$ gem install middleman
The program 'gem' is currently not installed. You can install it by typing:
sudo apt install ruby
gurujada@gurujada-To-be-filled-by-O-E-M:~$ sudo apt install ruby
[sudo] password for gurujada:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  fonts-lato javascript-common libjs-jquery libruby2.3 rake ruby-did-you-mean
  ruby-minitest ruby-net-telnet ruby-power-assert ruby-test-unit ruby2.3
  rubygems-integration
Suggested packages:
  apache2 | lighttpd | httpd ri ruby-dev bundler
The following NEW packages will be installed:
  fonts-lato javascript-common libjs-jquery libruby2.3 rake ruby
  ruby-did-you-mean ruby-minitest ruby-net-telnet ruby-power-assert
  ruby-test-unit ruby2.3 rubygems-integration
0 upgraded, 13 newly installed, 0 to remove and 11 not upgraded.
Need to get 6,042 kB of archives.
After this operation, 27.5 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 fonts-lato all 2.0-1 [2,693 kB]
Get:2 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 javascript-common all 11 [6,066 B]
Get:3 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 libjs-jquery all 1.11.3+dfsg-4 [161 kB]
Get:4 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 rubygems-integration all 1.10 [4,966 B]
Get:5 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 ruby-did-you-mean all 1.0.0-2 [8,390 B]
Get:6 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 ruby-minitest all 5.8.4-2 [36.6 kB]
Get:7 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 ruby-net-telnet all 0.1.1-2 [12.6 kB]
Get:8 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 ruby-power-assert all 0.2.7-1 [7,668 B]
Get:9 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 ruby-test-unit all 3.1.7-2 [60.3 kB]
Get:10 http://in.archive.ubuntu.com/ubuntu xenial-updates/main amd64 libruby2.3 amd64 2.3.1-2~16.04 [2,957 kB]
Get:11 http://in.archive.ubuntu.com/ubuntu xenial-updates/main amd64 ruby2.3 amd64 2.3.1-2~16.04 [40.9 kB]
Get:12 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 ruby all 1:2.3.0+1 [5,530 B]
Get:13 http://in.archive.ubuntu.com/ubuntu xenial/main amd64 rake all 10.5.0-2 [48.2 kB]
Fetched 6,042 kB in 25s (239 kB/s)
Selecting previously unselected package fonts-lato.
(Reading database ... 211722 files and directories currently installed.)
Preparing to unpack .../fonts-lato_2.0-1_all.deb ...
Unpacking fonts-lato (2.0-1) ...
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Preparing to unpack .../rubygems-integration_1.10_all.deb ...
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Processing triggers for fontconfig (2.11.94-0ubuntu1.1) ...
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Setting up fonts-lato (2.0-1) ...
Setting up javascript-common (11) ...
Setting up libjs-jquery (1.11.3+dfsg-4) ...
Setting up rubygems-integration (1.10) ...
Setting up ruby-did-you-mean (1.0.0-2) ...
Setting up ruby-minitest (5.8.4-2) ...
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gurujada@gurujada-To-be-filled-by-O-E-M:~$ gem install middleman
Fetching: bundler-1.12.5.gem (100%)
ERROR:  While executing gem ... (Gem::FilePermissionError)
    You don't have write permissions for the /var/lib/gems/2.3.0 directory.
gurujada@gurujada-To-be-filled-by-O-E-M:~$ cd example
gurujada@gurujada-To-be-filled-by-O-E-M:~/example$ middleman init
middleman: command not found
gurujada@gurujada-To-be-filled-by-O-E-M:~/example$ cd ..
gurujada@gurujada-To-be-filled-by-O-E-M:~$ ruby -v
ruby 2.3.1p112 (2016-04-26) [x86_64-linux-gnu]
gurujada@gurujada-To-be-filled-by-O-E-M:~$ whereis ruby
ruby: /usr/bin/ruby /usr/bin/ruby2.3 /usr/lib/ruby /usr/share/man/man1/ruby.1.gz
gurujada@gurujada-To-be-filled-by-O-E-M:~$