Using the OpenSSL library with macOS Sierra
Working with C++ libraries on a Mac can be a pain and OpenSSL, a very popular one that’s used in many other libraries, led me scrambling around the web and going through different StackOverflow posts, Github issues, and blog posts/forums trying to figure out a way to do it without reinstalling everything.
Usually, you would just install OpenSSL with Homebrew….
$ brew install openssl
And then link it…
$ brew link --force openssl
Warning: Refusing to link: openssl
Linking keg-only openssl means you may end up linking against the insecure,
deprecated system OpenSSL while using the headers from Homebrew's openssl.
Instead, pass the full include/library paths to your compiler e.g.:
But don’t worry! There’s a fix. Homebrew installs OpenSSL but doesn’t link it to /usr/local/include, where the compiler looks into during #include< …> Thus, you must manually link it instead:
$ ln -s /usr/local/opt/openssl/include/openssl /usr/local/include
You also might want to link:
$ ln -s /usr/local/Cellar/openssl/[version]/include/openssl /usr/bin/openssl
$ ln -s /usr/local/opt/openssl/lib/libssl.1.0.0.dylib /usr/local/lib/
An example of [version] is 1.0.2j. And just in case, check whether you compiler looks into /usr/local/include. For clang, it is:
clang -x c -v -E /dev/null
And it should output this if clang searches through /usr/local/include
#include <...> search starts here:
And you should be able to start using OpenSSL! This fix also doesn’t just work with your C++ project but any project(e.g. Ruby project) you are building that uses OpenSSL.
And just a reminder — remember to add -lssl and -lcrypto flags for your compiler.
I hope this guide helped solve a headache of yours! I’m pretty new at this and I’d like to get better — any response is welcome :)
Check out my other posts and tutorials!