Creating shared libraries in C++ for OSX

I just started programming in C++ and I've realized that I've been having to write the same code over and over again(mostly utility functions).

So, I'm trying to create a shared library and install it in PATH so that I could use the utility functions whenever I needed to.

Here's what I've done so far :-

Create a file utils.h with the following contents :-

#include<iostream> #include<string> std::string to_binary(int x); 

Create a file utils.cpp with the following contents :-

#include "utils.h" std::string to_binary(int x) { std::string binary = ""; while ( x > 0 ) { if ( x & 1 ) binary += "1"; else binary += "0"; x >>= 1; } return binary; } 

Follow the steps mentioned here :-

• Create the library object code : g++ -Wall -fPIC -c utils.cpp

But as the link above is meant for Linux it does not really work on OSX. Could someone suggest reading resources or suggest hints in how I could go about compiling and setting those objects in the path on an OSX machine?

Also, I'm guessing that there should be a way I can make this cross-platform(i.e. write a set of instructions(bash script) or a Makefile) so that I could use to compile this easily across platforms. Any hints on that?

2 Answers

Use -dynamiclib option to compile a dynamic library on OS X:

g++ -dynamiclib -o libutils.dylib utils.cpp 

And then use it in your client application:

g++ client.cpp -L/dir/ -lutils 

The link you posted is using C and the C compiler. Since you are building C++:

g++ -shared -o libYourLibraryName.so utils.o