To create a MEX-file:
Install a MATLAB®-supported compiler.
Assemble your functions and the MATLAB API functions into one or more C/C++ or Fortran source files.
Write a gateway function in one of your source files.
Use the MATLAB mex function, called a build script, to build a binary MEX-file.
Use your binary MEX-file like any MATLAB function.
If you have multiple compilers installed on your system, see Changing Default Compiler.