Install Socket.io on Ubuntu 18.04

Following this: https://github.com/socketio/socket.i...cpp/issues/258

Code:git clone --recurse-submodules https://github.com/socketio/socket.io-client-cpp.git
Cloning into 'socket.io-client-cpp'...
remote: Enumerating objects: 34, done.
remote: Counting objects: 100% (34/34), done.
remote: Compressing objects: 100% (28/28), done.
remote: Total 1152 (delta 9), reused 20 (delta 6), pack-reused 1118
Receiving objects: 100% (1152/1152), 985.06 KiB | 1.12 MiB/s, done.
Resolving deltas: 100% (644/644), done.
Submodule 'lib/asio' (https://github.com/chriskohlhoff/asio.git) registered for path 'lib/asio'
Submodule 'lib/catch' (https://github.com/philsquared/Catch.git) registered for path 'lib/catch'
Submodule 'lib/rapidjson' (https://github.com/miloyip/rapidjson.git) registered for path 'lib/rapidjson'
Submodule 'lib/websocketpp' (https://github.com/zaphoyd/websocketpp.git) registered for path 'lib/websocketpp'
Cloning into '/home/xyz/junk/dummy/socket.io-client-cpp/lib/asio'...
remote: Enumerating objects: 1606, done.
remote: Counting objects: 100% (1606/1606), done.
remote: Compressing objects: 100% (1094/1094), done.
remote: Total 55423 (delta 898), reused 756 (delta 502), pack-reused 53817
Receiving objects: 100% (55423/55423), 20.26 MiB | 4.80 MiB/s, done.
Resolving deltas: 100% (38453/38453), done.
Cloning into '/home/xyz/junk/dummy/socket.io-client-cpp/lib/catch'...
remote: Enumerating objects: 44, done.
remote: Counting objects: 100% (44/44), done.
remote: Compressing objects: 100% (38/38), done.
remote: Total 30206 (delta 13), reused 21 (delta 6), pack-reused 30162
Receiving objects: 100% (30206/30206), 19.17 MiB | 4.31 MiB/s, done.
Resolving deltas: 100% (21216/21216), done.
Cloning into '/home/xyz/junk/dummy/socket.io-client-cpp/lib/rapidjson'...
remote: Enumerating objects: 23262, done.
remote: Total 23262 (delta 0), reused 0 (delta 0), pack-reused 23262
Receiving objects: 100% (23262/23262), 27.56 MiB | 3.66 MiB/s, done.
Resolving deltas: 100% (17776/17776), done.
Cloning into '/home/xyz/junk/dummy/socket.io-client-cpp/lib/websocketpp'...
remote: Enumerating objects: 10, done.
remote: Counting objects: 100% (10/10), done.
remote: Compressing objects: 100% (10/10), done.
remote: Total 12630 (delta 2), reused 1 (delta 0), pack-reused 12620
Receiving objects: 100% (12630/12630), 8.79 MiB | 3.48 MiB/s, done.
Resolving deltas: 100% (7699/7699), done.
Submodule path 'lib/asio': checked out '230c0d2ae035c5ce1292233fcab03cea0d341264'
Submodule path 'lib/catch': checked out '9c07718b5f779bc1405f98ca6b5b693026f6eac7'
Submodule path 'lib/rapidjson': checked out 'a36110e11874bcf35af854940e0ce910c19a8b49'
Submodule 'thirdparty/gtest' (https://chromium.googlesource.com/external/googletest.git) registered for path 'lib/rapidjson/thirdparty/gtest'
Cloning into '/home/xyz/junk/dummy/socket.io-client-cpp/lib/rapidjson/thirdparty/gtest'...
remote: Total 4343 (delta 3383), reused 4343 (delta 3383)
Receiving objects: 100% (4343/4343), 1.19 MiB | 2.20 MiB/s, done.
Resolving deltas: 100% (3383/3383), done.
Submodule path 'lib/rapidjson/thirdparty/gtest': checked out '0476e154db5fab1721c2a0f32abf4aa773679b52'
Submodule path 'lib/websocketpp': checked out '56123c87598f8b1dd471be83ca841ceae07f95ba'
xyz@xyz:~/junk/dummy$
Ran cmake:

Code:xyz@xyz:~/junk/dummy/socket.io-client-cpp$ cmake -DCMAKE_CXX_FLAGS=-std=c++11 -DCMAKE_BUILD_TYPE=Debug -DOPENSSL_ROOT_DIR:STRING=/usr/local/ssl -DOPENSSL_VERSION:STRING=1.0.2 -DBOOST_INCLUDEDIR=/home/xyz/Documents/b_abcTechnologies/work/boost/boost_1_75_0 -DBOOST_LIBRARYDIR=/home/xyz/Documents/b_abcTechnologies/work/boost/boost_1_75_0/stage/lib -DBOOST_VER:STRING=1.75.0 ./
-- The C compiler identification is GNU 7.3.0
-- The CXX compiler identification is GNU 7.3.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found OpenSSL: /usr/local/ssl/lib/libcrypto.so (found version "1.0.2o")
-- Configuring done
-- Generating done
CMake Warning:
Manually-specified variables were not used by the project:

BOOST_INCLUDEDIR
BOOST_LIBRARYDIR
BOOST_VER

-- Build files have been written to: /home/xyz/junk/dummy/socket.io-client-cpp

xyz@xyz:~/junk/dummy/socket.io-client-cpp$ ls
API.md CMakeFiles CMakeLists.txt INSTALL_IOS.md lib Makefile src
CMakeCache.txt cmake_install.cmake examples INSTALL.md LICENSE README.md test

xyz@xyz:~/junk/dummy/socket.io-client-cpp$
Why did it say:

Code:
Manually-specified variables were not used by the project:

BOOST_INCLUDEDIR
BOOST_LIBRARYDIR
BOOST_VER
How is it going to find the boost then?

I ran make and sudo make install. They didn't show any errors.

This link says: https://github.com/socketio/socket.i...#without-cmake

that Quote:

Outputs is under ./build, link with the all static libs under ./build/lib and include headers under ./build/include in your client code where you want to use it.

Nothing of this sort was generated in my case.
Code:$ ls
API.md CMakeFiles CMakeLists.txt INSTALL_IOS.md INSTALL.md libsioclient.a LICENSE README.md test
CMakeCache.txt cmake_install.cmake examples install_manifest.txt lib libsioclient_tls.a Makefile srcWhat more information should I provide here?