Compiling and linking OpenSSL on Ubuntu vs OSX

Question

Attempt 1, Vanilla Link to Library

I\'m trying to use a patched version of OpenSSL (so DTLS is easier to use). OpenSSL is in

/usr/lo         


        

Answer 1

The problem with the header file not being found seems to be you mixing up your options. -L adds a path to the linker library search paths, while -I adds a directory to the preprocessor header file search path. Change the -L to -I to solve that problem:

$ gcc -I/usr/local/openssl-1.0.1c/include server.c -o server.o

Now the linker problem is because you erroneously use the -L option to tell the linker to look for libraries in the include path. You need to change that path to the directory where the libraries are, usually a lib subdirectory. Also, the linker wants libraries in reverse order of their dependencies, so place the libraries you want to link with last on the command line:

$ gcc -I/usr/local/openssl-1.0.1c/include server.c -o server.o \
    -L/usr/local/openssl-1.0.1c/lib -lssl -lcrypto