How Do Programming Languages Communicate with Each Other?

Languages don’t really talk to each other directly. Instead, everything gets compiled down to machine code, the only language the CPU understands. When code calls another piece of code, it’s just telling the CPU to jump to a memory address. For example, a C program accessing OpenGL still needs a way for the compiler to know where the OpenGL functions are, which is done through proper linking.

You can think of it in terms of inter-language communication via FFIs. For syscalls, many languages turn to libraries written in C to act as middlemen. For instance, Python can use `ctypes` to call C functions, allowing it to leverage powerful capabilities from lower-level languages.

You're not alone in this confusion! What’s crucial to understand is that code written in C or similar languages compiles to machine code. This simplifies how they interact with one another when calling functions. That said, they must agree on calling conventions—how arguments are passed to functions—so they know how to talk to each other properly.

In the end, regardless of the programming language, file operations involve calls to the operating system. C compiles these calls into machine code, Python uses an interpreter, and Java runs on bytecode, but they all reach the OS functions when the time comes. This ensures compatibility between any language and the file system.

It all boils down to the ABI (Application Binary Interface) of the OS or CPU you're on. The ABI defines how functions are called, including how to pass parameters. When languages like Python or Java want to interface with C, they just need to format their memory data correctly to communicate with the C functions. Most programming languages implement something called a Foreign Function Interface (FFI) to facilitate these cross-language calls.