Module Objects¶

PyTypeObject PyModule_Type¶: Part of the Stable ABI.
This instance of PyTypeObject represents the Python module type. This is exposed to Python programs as types.ModuleType.

int PyModule_Check(PyObject *p)¶: Return true if p is a module object, or a subtype of a module object. This function always succeeds.

int PyModule_CheckExact(PyObject *p)¶: Return true if p is a module object, but not a subtype of PyModule_Type. This function always succeeds.

PyObject *PyModule_NewObject(PyObject *name)¶

Return value: New reference. Part of the Stable ABI since version 3.7.

Return a new module object with module.__name__ set to name. The module’s __name__, __doc__, __package__ and __loader__ attributes are filled in (all but __name__ are set to None). The caller is responsible for setting a __file__ attribute.

Return NULL with an exception set on error.

Added in version 3.3.

Changed in version 3.4: __package__ and __loader__ are now set to None.

PyObject *PyModule_New(const char *name)¶: Return value: New reference. Part of the Stable ABI.
Similar to PyModule_NewObject(), but the name is a UTF-8 encoded string instead of a Unicode object.

PyObject *PyModule_GetDict(PyObject *module)¶

Return value: Borrowed reference. Part of the Stable ABI.

Return the dictionary object that implements module’s namespace; this object is the same as the __dict__ attribute of the module object. If module is not a module object (or a subtype of a module object), SystemError is raised and NULL is returned.

It is recommended extensions use other PyModule_* and PyObject_* functions rather than directly manipulate a module’s __dict__.

The returned reference is borrowed from the module; it is valid until the module is destroyed.

PyObject *PyModule_GetNameObject(PyObject *module)¶: Return value: New reference. Part of the Stable ABI since version 3.7.
Return module’s __name__ value. If the module does not provide one, or if it is not a string, SystemError is raised and NULL is returned.

Added in version 3.3.

const char *PyModule_GetName(PyObject *module)¶

Part of the Stable ABI.

Similar to PyModule_GetNameObject() but return the name encoded to 'utf-8'.

The returned buffer is only valid until the module is renamed or destroyed. Note that Python code may rename a module by setting its __name__ attribute.

PyModuleDef *PyModule_GetDef(PyObject *module)¶

Part of the Stable ABI.

Return a pointer to the PyModuleDef struct from which the module was created, or NULL if the module wasn’t created from a definition.

On error, return NULL with an exception set. Use PyErr_Occurred() to tell this case apart from a missing PyModuleDef.

PyObject *PyModule_GetFilenameObject(PyObject *module)¶: Return value: New reference. Part of the Stable ABI.
Return the name of the file from which module was loaded using module’s __file__ attribute. If this is not defined, or if it is not a string, raise SystemError and return NULL; otherwise return a reference to a Unicode object.

Added in version 3.2.

const char *PyModule_GetFilename(PyObject *module)¶

Part of the Stable ABI.

Similar to PyModule_GetFilenameObject() but return the filename encoded to ‘utf-8’.

The returned buffer is only valid until the module’s __file__ attribute is reassigned or the module is destroyed.

Deprecated since version 3.2: PyModule_GetFilename() raises UnicodeEncodeError on unencodable filenames, use PyModule_GetFilenameObject() instead.

Module definition¶

Modules defined using the C API are typically defined using an array of slots The slots provide a “description” of how a module should be created.

Changed in version 3.15.0a1 (unreleased): Previously, a PyModuleDef struct was necessary to define modules. The older way of defining modules is still available: consult either the Module definition struct section or earlier versions of this documentation if you plan to support earlier Python versions.

The slots array is usually used to define an extension module’s “main” module object (see Defining extension modules for details). It can also be used to create extension modules dynamically.

Unless specified otherwise, the same slot ID may not be repeated in an array of slots.

type PyModuleDef_Slot¶

int slot¶

A slot ID, chosen from the available values explained below.

An ID of 0 marks the end of a PyModuleDef_Slot array.

void *value¶

Value of the slot, whose meaning depends on the slot ID.

The value may not be NULL. To leave a slot out, omit the PyModuleDef_Slot entry entirely.

Added in version 3.5.

The available slot types are:

Description slots¶

Py_mod_name¶

Part of the Stable ABI since version 3.15.

Name for the new module, as a NUL-terminated UTF8-encoded const char *.

Note that modules are typically created using a ModuleSpec, and when they are, the name from the spec will be used instead of Py_mod_name. However, it is still recommended to include this slot for introspection and debugging purposes.

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_name instead to support previous versions.

Py_mod_doc¶: Part of the Stable ABI since version 3.15.
Docstring for the module, as a NUL-terminated UTF8-encoded const char *. Usually set to a docstring variable created with PyDoc_STRVAR.

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_doc instead to support previous versions.

Feature slots¶

Py_mod_abi¶

Part of the Stable ABI since version 3.15.

A pointer to a PyABIInfo structure that describes the ABI that the extension is using.

When the module is loaded, the PyABIInfo in this slot is checked using PyABIInfo_Check().

A suitable PyABIInfo variable can be defined using the PyABIInfo_VAR macro, as in:

PyABIInfo_VAR(abi_info);

static PyModuleDef_Slot mymodule_slots[] = {
   {Py_mod_abi, &abi_info},
   ...
};

Added in version 3.15.

Py_mod_multiple_interpreters¶

Specifies one of the following values:

Py_MOD_MULTIPLE_INTERPRETERS_NOT_SUPPORTED¶: The module does not support being imported in subinterpreters.

Py_MOD_MULTIPLE_INTERPRETERS_SUPPORTED¶: The module supports being imported in subinterpreters, but only when they share the main interpreter’s GIL. (See Isolating Extension Modules.)

Py_MOD_PER_INTERPRETER_GIL_SUPPORTED¶: The module supports being imported in subinterpreters, even when they have their own GIL. (See Isolating Extension Modules.)

This slot determines whether or not importing this module in a subinterpreter will fail.

Multiple Py_mod_multiple_interpreters slots may not be specified in one module definition.

If Py_mod_multiple_interpreters is not specified, the import machinery defaults to Py_MOD_MULTIPLE_INTERPRETERS_SUPPORTED.

Added in version 3.12.

Py_mod_gil¶

Specifies one of the following values:

Py_MOD_GIL_USED¶: The module depends on the presence of the global interpreter lock (GIL), and may access global state without synchronization.

Py_MOD_GIL_NOT_USED¶: The module is safe to run without an active GIL.

This slot is ignored by Python builds not configured with --disable-gil. Otherwise, it determines whether or not importing this module will cause the GIL to be automatically enabled. See Free-threaded CPython for more detail.

Multiple Py_mod_gil slots may not be specified in one module definition.

If Py_mod_gil is not specified, the import machinery defaults to Py_MOD_GIL_USED.

Added in version 3.13.

Creation and initialization slots¶

Py_mod_create¶

Specifies a function that is called to create the module object itself. The value pointer of this slot must point to a function of the signature:

PyObject *create_module(PyObject *spec, PyModuleDef *def)¶

The function will be called with:

spec: a ModuleSpec-like object, meaning that any attributes defined for importlib.machinery.ModuleSpec have matching semantics. However, any of the attributes may be missing.
def: NULL, or the module definition if the module is created from one.

The function should return a new module object, or set an error and return NULL.

This function should be kept minimal. In particular, it should not call arbitrary Python code, as trying to import the same module again may result in an infinite loop.

If Py_mod_create is not specified, the import machinery will create a normal module object using PyModule_New(). The name is taken from spec, not the definition, to allow extension modules to dynamically adjust to their place in the module hierarchy and be imported under different names through symlinks, all while sharing a single module definition.

There is no requirement for the returned object to be an instance of PyModule_Type. Any type can be used, as long as it supports setting and getting import-related attributes. However, only PyModule_Type instances may be returned if the PyModuleDef has non-NULL m_traverse, m_clear, m_free; non-zero m_size; or slots other than Py_mod_create.

Changed in version 3.15.0a1 (unreleased): The slots argument may be ModuleSpec-like object, rather than a true ModuleSpec instance. Note that previous versions of CPython did not enforce this.

Py_mod_exec¶

Specifies a function that is called to execute the module. This is equivalent to executing the code of a Python module: typically, this function adds classes and constants to the module. The signature of the function is:

int exec_module(PyObject *module)¶

See the Support functions section for some useful functions to call.

For backwards compatibility, the PyModuleDef.m_slots array may contain multiple Py_mod_exec slots; these are processed in the order they appear in the array. Elsewhere (that is, in arguments to PyModule_FromSlotsAndSpec() and in return values of PyModExport_<name>), repeating the slot is not allowed.

Changed in version 3.15.0a1 (unreleased): Repeated Py_mod_exec slots are disallowed, except in PyModuleDef.m_slots.

Py_mod_methods¶

Part of the Stable ABI since version 3.15.

A pointer to a table of module-level functions, as an array of PyMethodDef values suitable as the functions argument to PyModule_AddFunctions().

Like other slot IDs, a slots array may only contain one Py_mod_methods entry. To add functions from multiple PyMethodDef arrays, call PyModule_AddFunctions() in the Py_mod_exec function.

The table must be statically allocated (or otherwise guaranteed to outlive the module object).

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_methods instead to support previous versions.

Slots for defining module state¶

See Module state for an explanation of module state.

Py_mod_state_size¶

Part of the Stable ABI since version 3.15.

Size of the module state, cast to a void* pointer.

Setting this to a non-negative value means that the module can be re-initialized and specifies the additional amount of memory it requires for its state.

Setting the size to -1 means that the module does not support sub-interpreters, because it has global state. Negative size is only allowed when using legacy single-phase initialization or when creating modules dynamically.

See PEP 3121 for more details.

Use PyModule_GetStateSize() to retrieve the size of a given module.

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_size instead to support previous versions.

Py_mod_state_traverse¶

Part of the Stable ABI since version 3.15.

A traversal function to call during GC traversal of the module object.

The signature of the function, and meanings of the arguments, is similar as for PyTypeObject.tp_traverse:

int traverse_module_state(PyObject *module, visitproc visit, void *arg)¶

This function is not called if the module state was requested but is not allocated yet. This is the case immediately after the module is created and before the module is executed (Py_mod_exec function). More precisely, this function is not called if the state size (Py_mod_state_size) is greater than 0 and the module state (as returned by PyModule_GetState()) is NULL.

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_size instead to support previous versions.

Py_mod_state_clear¶

Part of the Stable ABI since version 3.15.

A clear function to call during GC clearing of the module object.

The signature of the function is:

int clear_module_state(PyObject *module)¶

This function is not called if the module state was requested but is not allocated yet. This is the case immediately after the module is created and before the module is executed (Py_mod_exec function). More precisely, this function is not called if the state size (Py_mod_state_size) is greater than 0 and the module state (as returned by PyModule_GetState()) is NULL.

Like PyTypeObject.tp_clear, this function is not always called before a module is deallocated. For example, when reference counting is enough to determine that an object is no longer used, the cyclic garbage collector is not involved and the Py_mod_state_free function is called directly.

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_clear instead to support previous versions.

Py_mod_state_free¶

Part of the Stable ABI since version 3.15.

A function to call during deallocation of the module object.

The signature of the function is:

int free_module_state(PyObject *module)¶

This function is not called if the module state was requested but is not allocated yet. This is the case immediately after the module is created and before the module is executed (Py_mod_exec function). More precisely, this function is not called if the state size (Py_mod_state_size) is greater than 0 and the module state (as returned by PyModule_GetState()) is NULL.

Added in version 3.15.0a1 (unreleased): Use PyModuleDef.m_free instead to support previous versions.

Py_mod_token¶

Part of the Stable ABI since version 3.15.

A pointer intended to identify of the module state’s memory layout. See the Module token section for details.

This slot is not needed for typical extensions; it exists for specialized use cases – namely, dynamically created modules. If you use the slot, you must ensure that:

The pointer outlives the class, so it’s not reused for something else while the class exists.
It “belongs” to the extension module where the class lives, so it will not clash with other extensions. (Preventing clashes with other modules defined in the same extension is the extension’s responsibility; you don’t need to use the token for this.)
If the token points to a PyModuleDef struct, the module should behave as if it was created from that PyModuleDef. In particular, the module state must have matching layout and semantics.

Modules created from PyModuleDef allways use the address of the PyModuleDef as the token; Py_mod_token cannot be used in PyModuleDef.m_slots.

Added in version 3.15.0a1 (unreleased).

Module state¶

Extension modules can have module state – a piece of memory that is allocated on module creation, and freed when the module object is deallocated. The module state is specified using dedicated slots.

Unlike the module’s Python attributes, Python code cannot replace or delete data stored in module state.

Keeping per-module information in attributes and module state, rather than in static globals, makes module objects isolated and safer for use in multiple sub-interpreters. It also helps Python do an orderly clean-up when it shuts down.

Extensions that keep references to Python objects as part of module state must implement Py_mod_state_traverse and Py_mod_state_clear functions to avoid reference leaks.

To retrieve the state from a given module, use the following functions:

void *PyModule_GetState(PyObject *module)¶

Part of the Stable ABI.

Return the “state” of the module, that is, a pointer to the block of memory allocated at module creation time, or NULL. See Py_mod_size.

On error, return NULL with an exception set. Use PyErr_Occurred() to tell this case apart from a missing PyModuleDef.

int PyModule_GetStateSize(PyObject*, Py_ssize_t *result)¶

Part of the Stable ABI since version 3.15.

Set *result to the size of the module’s state, as specified using Py_mod_size (or PyModuleDef.m_size), and return 0.

On error, set *result to -1, and return -1 with an exception set.

Added in version 3.15.0a1 (unreleased).

Module token¶

Each module has an associated token, a pointer-sized value intended to identify of the module state’s memory layout. This means that if you have a module object, but you are not sure if it “belongs” to your extension, you can check using code like this:

PyObject *module = <the module in question>

void *module_token;
if (PyModule_GetToken(module, &module_token) < 0) {
    return NULL;
}
if (module_token != your_token) {
    if (!PyErr_Occurred()) {
        PyErr_SetString(PyExc_ValueError, "unexpected module")
    }
    return NULL;
}

// Now it's safe to cast: this module's state has the expected memory layout
struct my_state state = (struct my_state*)PyModule_GetState(module)
if (state == NULL) {
    return NULL;
}

A module’s token – and the your_token value to use in the above code – is:

For modules defined with the Py_mod_token slot: the value of that slot;
For modules created from an PyModExport_* export hook: the slots array that the export hook returned (unless overriden with Py_mod_token).
For modules created with PyModuleDef: the address of that PyModuleDef.

int PyModule_GetToken(PyObject *module, void **result)¶

Part of the Stable ABI since version 3.15.

Set *result to the module’s token and return 0. See Py_mod_token for information about module tokens.

On error, set *result to NULL, and return -1 with an exception set.

Added in version 3.15.0a1 (unreleased).

Creating extension modules dynamically¶

The following functions may be used to create an extension module dynamically, rather than from an extension’s export hook.

PyObject *PyModule_FromSlotsAndSpec(const PyModuleDef_Slot *slots, PyObject *spec)¶

Part of the Stable ABI since version 3.15.

Create a new module object, given an array of slots and the ModuleSpec spec.

The slots argument must point to an array of PyModuleDef_Slot structures, terminated by an entry slot with slot ID of 0 (typically written as {0} or {0, NULL} in C). The slots argument may not be NULL.

The spec argument may be any ModuleSpec-like object, as described in Py_mod_create documentation. Currently, the spec must have a name attribute.

On success, return the new module. On error, return NULL with an exception set.

Note that this does not process the module’s execution slot (Py_mod_exec). Both PyModule_FromSlotsAndSpec() and PyModule_Exec() must be called to fully initialize a module. (Python’s default import machinery takes additional steps between these two calls, such as inserting the module object in sys.modules and setting import-related attributes.)

The slots array only needs to be valid for the duration of the PyModule_FromSlotsAndSpec() call. In particular, it may be heap-allocated.

Added in version 3.15.0a1 (unreleased).

int PyModule_Exec(PyObject*)¶

Part of the Stable ABI since version 3.15.

Execute the Py_mod_exec slot(s) of the given module.

On success, return 0. On error, return -1 with an exception set.

Added in version 3.15.0a1 (unreleased).

Module definition struct¶

Traditionally, extension modules were defined using a module definition as the “description” of how a module should be created. Rather than using an array of slots directly, the definition has dedicated members for most common functionality, and allows additional slots as an extension mechanism.

This way of defining modules is still available and there are no plans to remove it.

type PyModuleDef¶

Part of the Stable ABI (including all members).

The module definition struct, which holds information needed to create a module object.

This structure must be statically allocated (or be otherwise guaranteed to be valid while any modules created from it exist). Usually, there is only one variable of this type for each extension module defined this way.

PyModuleDef_Base m_base¶: Always initialize this member to PyModuleDef_HEAD_INIT.

const char *m_name¶

const char *m_doc¶

Py_ssize_t m_size¶

PyMethodDef *m_methods¶

These members correspond to the Py_mod_name, Py_mod_doc, Py_mod_state_size, and Py_mod_methods slots, respectively.

Setting these members to NULL is equivalent to omitting the corresponding slots.

PyModuleDef_Slot *m_slots¶

An array of additional slots, terminated by a {0, NULL} entry.

This array may not contain slots corresponding to PyModuleDef members. For example, you cannot use a Py_mod_name slot; the module name must be given as PyModuleDef.m_name.

Changed in version 3.5: Prior to version 3.5, this member was always set to NULL, and was defined as:

inquiry m_reload¶

const char m_doc Py_ssize_t m_size PyMethodDef m_methods traverseproc m_traverse inquiry m_clear freefunc m_free

traverseproc m_traverse¶

inquiry m_clear¶

freefunc m_free¶

These members correspond to the Py_mod_state_traverse, Py_mod_state_clear, and Py_mod_state_free slots, respectively.

Setting these members to NULL is equivalent to omitting the corresponding slots.

Changed in version 3.9: m_traverse, m_clear and m_free functions are longer called before the module state is allocated.

The following API can be used to create modules from a PyModuleDef struct:

PyObject *PyModule_Create(PyModuleDef *def)¶: Return value: New reference.
Create a new module object, given the definition in def. This is a macro that calls PyModule_Create2() with module_api_version set to PYTHON_API_VERSION, or to PYTHON_ABI_VERSION if using the limited API.

PyObject *PyModule_Create2(PyModuleDef *def, int module_api_version)¶

Return value: New reference. Part of the Stable ABI.

Create a new module object, given the definition in def, assuming the API version module_api_version. If that version does not match the version of the running interpreter, a RuntimeWarning is emitted.

Return NULL with an exception set on error.

This function does not support slots. The m_slots member of def must be NULL.

Note

Most uses of this function should be using PyModule_Create() instead; only use this if you are sure you need it.

PyObject *PyModule_FromDefAndSpec(PyModuleDef *def, PyObject *spec)¶: Return value: New reference.
This macro calls PyModule_FromDefAndSpec2() with module_api_version set to PYTHON_API_VERSION, or to PYTHON_ABI_VERSION if using the limited API.

Added in version 3.5.

PyObject *PyModule_FromDefAndSpec2(PyModuleDef *def, PyObject *spec, int module_api_version)¶

Return value: New reference. Part of the Stable ABI since version 3.7.

Create a new module object, given the definition in def and the ModuleSpec spec, assuming the API version module_api_version. If that version does not match the version of the running interpreter, a RuntimeWarning is emitted.

Return NULL with an exception set on error.

Note that this does not process execution slots (Py_mod_exec). Both PyModule_FromDefAndSpec and PyModule_ExecDef must be called to fully initialize a module.

Note

Most uses of this function should be using PyModule_FromDefAndSpec() instead; only use this if you are sure you need it.

Added in version 3.5.

int PyModule_ExecDef(PyObject *module, PyModuleDef *def)¶: Part of the Stable ABI since version 3.7.
Process any execution slots (Py_mod_exec) given in def.

Added in version 3.5.

PYTHON_API_VERSION¶

The C API version. Defined for backwards compatibility.

Currently, this constant is not updated in new Python versions, and is not useful for versioning. This may change in the future.

PYTHON_ABI_VERSION¶

Defined as 3 for backwards compatibility.

Currently, this constant is not updated in new Python versions, and is not useful for versioning. This may change in the future.

Support functions¶

The following functions are provided to help initialize a module object. They are intended for a module’s execution slot (Py_mod_exec), the initialization function for legacy single-phase initialization, or code that creates modules dynamically.

int PyModule_AddObjectRef(PyObject *module, const char *name, PyObject *value)¶

Part of the Stable ABI since version 3.10.

Add an object to module as name. This is a convenience function which can be used from the module’s initialization function.

On success, return 0. On error, raise an exception and return -1.

Example usage:

static int
add_spam(PyObject *module, int value)
{
    PyObject *obj = PyLong_FromLong(value);
    if (obj == NULL) {
        return -1;
    }
    int res = PyModule_AddObjectRef(module, "spam", obj);
    Py_DECREF(obj);
    return res;
 }

To be convenient, the function accepts NULL value with an exception set. In this case, return -1 and just leave the raised exception unchanged.

The example can also be written without checking explicitly if obj is NULL:

static int
add_spam(PyObject *module, int value)
{
    PyObject *obj = PyLong_FromLong(value);
    int res = PyModule_AddObjectRef(module, "spam", obj);
    Py_XDECREF(obj);
    return res;
 }

Note that Py_XDECREF() should be used instead of Py_DECREF() in this case, since obj can be NULL.

The number of different name strings passed to this function should be kept small, usually by only using statically allocated strings as name. For names that aren’t known at compile time, prefer calling PyUnicode_FromString() and PyObject_SetAttr() directly. For more details, see PyUnicode_InternFromString(), which may be used internally to create a key object.

Added in version 3.10.

int PyModule_Add(PyObject *module, const char *name, PyObject *value)¶

Part of the Stable ABI since version 3.13.

Similar to PyModule_AddObjectRef(), but “steals” a reference to value. It can be called with a result of function that returns a new reference without bothering to check its result or even saving it to a variable.

Example usage:

if (PyModule_Add(module, "spam", PyBytes_FromString(value)) < 0) {
    goto error;
}

Added in version 3.13.

int PyModule_AddObject(PyObject *module, const char *name, PyObject *value)¶

Part of the Stable ABI.

Similar to PyModule_AddObjectRef(), but steals a reference to value on success (if it returns 0).

The new PyModule_Add() or PyModule_AddObjectRef() functions are recommended, since it is easy to introduce reference leaks by misusing the PyModule_AddObject() function.

Note

Unlike other functions that steal references, PyModule_AddObject() only releases the reference to value on success.

This means that its return value must be checked, and calling code must Py_XDECREF() value manually on error.

Example usage:

PyObject *obj = PyBytes_FromString(value);
if (PyModule_AddObject(module, "spam", obj) < 0) {
    // If 'obj' is not NULL and PyModule_AddObject() failed,
    // 'obj' strong reference must be deleted with Py_XDECREF().
    // If 'obj' is NULL, Py_XDECREF() does nothing.
    Py_XDECREF(obj);
    goto error;
}
// PyModule_AddObject() stole a reference to obj:
// Py_XDECREF(obj) is not needed here.

Deprecated since version 3.13: PyModule_AddObject() is soft deprecated.

int PyModule_AddIntConstant(PyObject *module, const char *name, long value)¶

Part of the Stable ABI.

Add an integer constant to module as name. This convenience function can be used from the module’s initialization function. Return -1 with an exception set on error, 0 on success.

This is a convenience function that calls PyLong_FromLong() and PyModule_AddObjectRef(); see their documentation for details.

int PyModule_AddStringConstant(PyObject *module, const char *name, const char *value)¶

Part of the Stable ABI.

Add a string constant to module as name. This convenience function can be used from the module’s initialization function. The string value must be NULL-terminated. Return -1 with an exception set on error, 0 on success.

This is a convenience function that calls PyUnicode_InternFromString() and PyModule_AddObjectRef(); see their documentation for details.

PyModule_AddIntMacro(module, macro)¶: Add an int constant to module. The name and the value are taken from macro. For example PyModule_AddIntMacro(module, AF_INET) adds the int constant AF_INET with the value of AF_INET to module. Return -1 with an exception set on error, 0 on success.

PyModule_AddStringMacro(module, macro)¶: Add a string constant to module.

int PyModule_AddType(PyObject *module, PyTypeObject *type)¶: Part of the Stable ABI since version 3.10.
Add a type object to module. The type object is finalized by calling internally PyType_Ready(). The name of the type object is taken from the last component of tp_name after dot. Return -1 with an exception set on error, 0 on success.

Added in version 3.9.

int PyModule_AddFunctions(PyObject *module, PyMethodDef *functions)¶

Part of the Stable ABI since version 3.7.

Add the functions from the NULL terminated functions array to module. Refer to the PyMethodDef documentation for details on individual entries (due to the lack of a shared module namespace, module level “functions” implemented in C typically receive the module as their first parameter, making them similar to instance methods on Python classes).

This function is called automatically when creating a module from PyModuleDef (such as when using Multi-phase initialization, PyModule_Create, or PyModule_FromDefAndSpec). Some module authors may prefer defining functions in multiple PyMethodDef arrays; in that case they should call this function directly.

The functions array must be statically allocated (or otherwise guaranteed to outlive the module object).

Added in version 3.5.

int PyModule_SetDocString(PyObject *module, const char *docstring)¶: Part of the Stable ABI since version 3.7.
Set the docstring for module to docstring. This function is called automatically when creating a module from PyModuleDef (such as when using Multi-phase initialization, PyModule_Create, or PyModule_FromDefAndSpec).

Added in version 3.5.

int PyUnstable_Module_SetGIL(PyObject *module, void *gil)¶: This is Unstable API. It may change without warning in minor releases.

Indicate that module does or does not support running without the global interpreter lock (GIL), using one of the values from Py_mod_gil. It must be called during module’s initialization function when using Legacy single-phase initialization. If this function is not called during module initialization, the import machinery assumes the module does not support running without the GIL. This function is only available in Python builds configured with --disable-gil. Return -1 with an exception set on error, 0 on success.

Added in version 3.13.

Module lookup (single-phase initialization)¶

The legacy single-phase initialization initialization scheme creates singleton modules that can be looked up in the context of the current interpreter. This allows the module object to be retrieved later with only a reference to the module definition.

These functions will not work on modules created using multi-phase initialization, since multiple such modules can be created from a single definition.

PyObject *PyState_FindModule(PyModuleDef *def)¶: Return value: Borrowed reference. Part of the Stable ABI.
Returns the module object that was created from def for the current interpreter. This method requires that the module object has been attached to the interpreter state with PyState_AddModule() beforehand. In case the corresponding module object is not found or has not been attached to the interpreter state yet, it returns NULL.

int PyState_AddModule(PyObject *module, PyModuleDef *def)¶

Part of the Stable ABI since version 3.3.

Attaches the module object passed to the function to the interpreter state. This allows the module object to be accessible via PyState_FindModule().

Only effective on modules created using single-phase initialization.

Python calls PyState_AddModule automatically after importing a module that uses single-phase initialization, so it is unnecessary (but harmless) to call it from module initialization code. An explicit call is needed only if the module’s own init code subsequently calls PyState_FindModule. The function is mainly intended for implementing alternative import mechanisms (either by calling it directly, or by referring to its implementation for details of the required state updates).

If a module was attached previously using the same def, it is replaced by the new module.

The caller must have an attached thread state.

Return -1 with an exception set on error, 0 on success.

Added in version 3.3.

int PyState_RemoveModule(PyModuleDef *def)¶

Part of the Stable ABI since version 3.3.

Removes the module object created from def from the interpreter state. Return -1 with an exception set on error, 0 on success.

The caller must have an attached thread state.

Added in version 3.3.

Module Objects¶

Module definition¶

Description slots¶

Feature slots¶

Creation and initialization slots¶

Slots for defining module state¶

Module state¶

Module token¶

Creating extension modules dynamically¶

Module definition struct¶

Support functions¶

Module lookup (single-phase initialization)¶

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