What is the best way to call C/C++ code from other languages such as Java, PHP, Perl, Python, etc?

Question

What is the best way to call C/C++ from other languages such as Java, Python, Perl, PHP, etc?

Answer 1

Use Swig, it allows you to generate code for multiple languages that calls any C/C++ functions. http://www.swig.org/

Answer 2

That really depends on the language... some languages can bind directly to c/c++ libraries, others such as java needs to have explicit interfaces written. If you are trying to solve a specific problem, I would suggest that you provide more details about what you are trying to do.

Answer 3

It's going to depend on the language and what sort of integration you want.

All of those languages will let you execute an system command, so you could build your C into an executable, and invoke it like a command. In Python:

os.system("myccode -v args etc")

The downside of this method is that you don't share any memory state, or return much information, and you have the overhead of spinning up a process. On the plus side, it's usable everywhere, and very low-tech.

Each language has their own mechanism for invoking C within the same process. Python for example has C API, and you can build your C code into a Python extension. This allows for a very tight integration, but is more work, both in learning the C API, and in carefully writing the code to not leak memory.

Python also provides ctypes, which can invoke C DLLs. This is a bit easier than a full C extension, but doesn't provide all the same opportunities for integration.

Answer 4

From Perl

Inline::C
Inline::CPP
Inline::Java
Inline::Python
Inline::Lua

excerpt from Inline::C-Cookbook:

use Inline C => <<'END_C';

  void greet() {
    printf("Hello, world\n");
  }
END_C

greet;