How do I access a module written in Python from C?

You can get a pointer to the module object by calling PyImport_ImportModule:

module = PyImport_ImportModule("mymodule");

If the module hasn’t been imported yet (i.e. it is not yet present in sys.modules), this initializes the module; otherwise it simply returns the value of sys.modules[“<modulename>”]. Note that it doesn’t enter the module into any namespace — it only ensures it has been initialized and is stored in sys.modules.

You can then access the module’s attributes (i.e. any name defined in the module) as follows:

attr = PyObject_GetAttrString(module, "name");

Calling PyObject_SetAttrString to assign to variables in the module also works.

CATEGORY: extending