5.4. Importing Modules¶

PyObject* PyImport_ImportModule(const char *name)¶

PyObject* PyImport_ImportModuleNoBlock(const char *name)¶

This version of PyImport_ImportModule() does not block. It’s intended to be used in C functions that import other modules to execute a function. The import may block if another thread holds the import lock. The function PyImport_ImportModuleNoBlock() never blocks. It first tries to fetch the module from sys.modules and falls back to PyImport_ImportModule() unless the lock is held, in which case the function will raise an ImportError.

New in version 2.6.

PyObject* PyImport_ImportModuleEx(char *name, PyObject *globals, PyObject *locals, PyObject *fromlist)¶

PyObject* PyImport_ImportModuleLevel(char *name, PyObject *globals, PyObject *locals, PyObject *fromlist, int level)¶

Import a module. This is best described by referring to the built-in Python function __import__(), as the standard __import__() function calls this function directly.

The return value is a new reference to the imported module or top-level package, or NULL with an exception set on failure. Like for __import__(), the return value when a submodule of a package was requested is normally the top-level package, unless a non-empty fromlist was given.

New in version 2.5.

PyObject* PyImport_Import(PyObject *name)¶

PyObject* PyImport_ReloadModule(PyObject *m)¶

PyObject* PyImport_AddModule(const char *name)¶

Return the module object corresponding to a module name. The name argument may be of the form package.module. First check the modules dictionary if there’s one there, and if not, create a new one and insert it in the modules dictionary. Return NULL with an exception set on failure.

Note

This function does not load or import the module; if the module wasn’t already loaded, you will get an empty module object. Use PyImport_ImportModule() or one of its variants to import a module. Package structures implied by a dotted name for name are not created if not already present.

PyObject* PyImport_ExecCodeModule(char *name, PyObject *co)¶

PyObject* PyImport_ExecCodeModuleEx(char *name, PyObject *co, char *pathname)¶

Like PyImport_ExecCodeModule(), but the __file__ attribute of the module object is set to pathname if it is non-NULL.

long PyImport_GetMagicNumber()¶

Return the magic number for Python bytecode files (a.k.a. .pyc and .pyo files). The magic number should be present in the first four bytes of the bytecode file, in little-endian byte order.

PyObject* PyImport_GetModuleDict()¶

Return the dictionary used for the module administration (a.k.a. sys.modules). Note that this is a per-interpreter variable.

PyObject* PyImport_GetImporter(PyObject *path)¶

Return an importer object for a sys.path/pkg.__path__ item path, possibly by fetching it from the sys.path_importer_cache dict. If it wasn’t yet cached, traverse sys.path_hooks until a hook is found that can handle the path item. Return None if no hook could; this tells our caller it should fall back to the built-in import mechanism. Cache the result in sys.path_importer_cache. Return a new reference to the importer object.

New in version 2.6.

void _PyImport_Init()¶

Initialize the import mechanism. For internal use only.

void PyImport_Cleanup()¶

Empty the module table. For internal use only.

void _PyImport_Fini()¶

Finalize the import mechanism. For internal use only.

PyObject* _PyImport_FindExtension(char *, char *)¶

For internal use only.

PyObject* _PyImport_FixupExtension(char *, char *)¶

For internal use only.

int PyImport_ImportFrozenModule(char *name)¶

Load a frozen module named name. Return 1 for success, 0 if the module is not found, and -1 with an exception set if the initialization failed. To access the imported module on a successful load, use PyImport_ImportModule(). (Note the misnomer — this function would reload the module if it was already imported.)

struct _frozen¶

struct _frozen* PyImport_FrozenModules¶

This pointer is initialized to point to an array of struct _frozen records, terminated by one whose members are all NULL or zero. When a frozen module is imported, it is searched in this table. Third-party code could play tricks with this to provide a dynamically created collection of frozen modules.

int PyImport_AppendInittab(const char *name, void (*initfunc)(void))¶

Add a single module to the existing table of built-in modules. This is a convenience wrapper around PyImport_ExtendInittab(), returning -1 if the table could not be extended. The new module can be imported by the name name, and uses the function initfunc as the initialization function called on the first attempted import. This should be called before Py_Initialize().

struct _inittab¶

Structure describing a single entry in the list of built-in modules. Each of these structures gives the name and initialization function for a module built into the interpreter. Programs which embed Python may use an array of these structures in conjunction with PyImport_ExtendInittab() to provide additional built-in modules. The structure is defined in Include/import.h as:

struct _inittab {
    char *name;
    void (*initfunc)(void);
};

int PyImport_ExtendInittab(struct _inittab *newtab)¶

Add a collection of modules to the table of built-in modules. The newtab array must end with a sentinel entry which contains NULL for the name field; failure to provide the sentinel value can result in a memory fault. Returns 0 on success or -1 if insufficient memory could be allocated to extend the internal table. In the event of failure, no modules are added to the internal table. This should be called before Py_Initialize().