The functions in this chapter perform various utility tasks, ranging from helping C code be more portable across platforms, using Python modules from C, and parsing function arguments and constructing Python values from C values.
Return true (nonzero) if the standard I/O file fp with name filename is deemed interactive. This is the case for files for which isatty(fileno(fp)) is true. If the global flag Py_InteractiveFlag is true, this function also returns true if the filename pointer is NULL or if the name is equal to one of the strings '<stdin>' or '???'.
Return the time of last modification of the file filename. The result is encoded in the same way as the timestamp returned by the standard C library function time().
Function to update some internal state after a process fork; this should be called in the new process if the Python interpreter will continue to be used. If a new executable is loaded into the new process, this function does not need to be called.
Return true when the interpreter runs out of stack space. This is a reliable check, but is only available when USE_STACKCHECK is defined (currently on Windows using the Microsoft Visual C++ compiler). USE_STACKCHECK will be defined automatically; you should never change the definition in your own code.
Return the current signal handler for signal i. This is a thin wrapper around either sigaction() or signal(). Do not call those functions directly! PyOS_sighandler_t is a typedef alias for void (*)(int).
Set the signal handler for signal i to be h; return the old signal handler. This is a thin wrapper around either sigaction() or signal(). Do not call those functions directly! PyOS_sighandler_t is a typedef alias for void (*)(int).
These are utility functions that make functionality from the sys module accessible to C code. They all work with the current interpreter thread’s sys module’s dict, which is contained in the internal thread state structure.
Return the object name from the sys module or NULL if it does not exist, without setting an exception.
Return the FILE* associated with the object name in the sys module, or def if name is not in the module or is not associated with a FILE*.
Set name in the sys module to v unless v is NULL, in which case name is deleted from the sys module. Returns 0 on success, -1 on error.
Reset sys.warnoptions to an empty list.
Append s to sys.warnoptions.
Set sys.path to a list object of paths found in path which should be a list of paths separated with the platform’s search path delimiter (: on Unix, ; on Windows).
Write the output string described by format to sys.stdout. No exceptions are raised, even if truncation occurs (see below).
format should limit the total size of the formatted output string to 1000 bytes or less – after 1000 bytes, the output string is truncated. In particular, this means that no unrestricted “%s” formats should occur; these should be limited using “%.<N>s” where <N> is a decimal number calculated so that <N> plus the maximum size of other formatted text does not exceed 1000 bytes. Also watch out for “%f”, which can print hundreds of digits for very large numbers.
If a problem occurs, or sys.stdout is unset, the formatted message is written to the real (C level) stdout.
As above, but write to sys.stderr or stderr instead.
Print a fatal error message and kill the process. No cleanup is performed. This function should only be invoked when a condition is detected that would make it dangerous to continue using the Python interpreter; e.g., when the object administration appears to be corrupted. On Unix, the standard C library function abort() is called which will attempt to produce a core file.
Exit the current process. This calls Py_Finalize() and then calls the standard C library function exit(status).
Register a cleanup function to be called by Py_Finalize(). The cleanup function will be called with no arguments and should return no value. At most 32 cleanup functions can be registered. When the registration is successful, Py_AtExit() returns 0; on failure, it returns -1. The cleanup function registered last is called first. Each cleanup function will be called at most once. Since Python’s internal finalization will have completed before the cleanup function, no Python APIs should be called by func.
This is a simplified interface to PyImport_ImportModuleEx() below, leaving the globals and locals arguments set to NULL. When the name argument contains a dot (when it specifies a submodule of a package), the fromlist argument is set to the list ['*'] so that the return value is the named module rather than the top-level package containing it as would otherwise be the case. (Unfortunately, this has an additional side effect when name in fact specifies a subpackage instead of a submodule: the submodules specified in the package’s __all__ variable are loaded.) Return a new reference to the imported module, or NULL with an exception set on failure. Before Python 2.4, the module may still be created in the failure case — examine sys.modules to find out. Starting with Python 2.4, a failing import of a module no longer leaves the module in sys.modules.
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 (before Python 2.4, the module may still be created in this case). 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.
Failing imports remove incomplete module objects, like with PyImport_ImportModule().
This is a higher-level interface that calls the current “import hook function”. It invokes the __import__() function from the __builtins__ of the current globals. This means that the import is done using whatever import hooks are installed in the current environment.
Reload a module. Return a new reference to the reloaded module, or NULL with an exception set on failure (the module still exists in this case).
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.
Given a module name (possibly of the form package.module) and a code object read from a Python bytecode file or obtained from the built-in function compile(), load the module. Return a new reference to the module object, or NULL with an exception set if an error occurred. Before Python 2.4, the module could still be created in error cases. Starting with Python 2.4, name is removed from sys.modules in error cases, and even if name was already in sys.modules on entry to PyImport_ExecCodeModule(). Leaving incompletely initialized modules in sys.modules is dangerous, as imports of such modules have no way to know that the module object is an unknown (and probably damaged with respect to the module author’s intents) state.
This function will reload the module if it was already imported. See PyImport_ReloadModule() for the intended way to reload a module.
If name points to a dotted name of the form package.module, any package structures not already created will still not be created.
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.
Return the dictionary used for the module administration (a.k.a. sys.modules). Note that this is a per-interpreter variable.
Initialize the import mechanism. For internal use only.
Empty the module table. For internal use only.
Finalize the import mechanism. For internal use only.
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.)
This is the structure type definition for frozen module descriptors, as generated by the freeze utility (see Tools/freeze/ in the Python source distribution). Its definition, found in Include/import.h, is:
struct _frozen {
char *name;
unsigned char *code;
int size;
};
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.
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().
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);
};
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().
These routines allow C code to work with serialized objects using the same data format as the marshal module. There are functions to write data into the serialization format, and additional functions that can be used to read the data back. Files used to store marshalled data must be opened in binary mode.
Numeric values are stored with the least significant byte first.
The module supports two versions of the data format: version 0 is the historical version, version 1 (new in Python 2.4) shares interned strings in the file, and upon unmarshalling. Py_MARSHAL_VERSION indicates the current file format (currently 1).
Marshal a long integer, value, to file. This will only write the least-significant 32 bits of value; regardless of the size of the native long type. version indicates the file format.
Marshal a Python object, value, to file. version indicates the file format.
Return a string object containing the marshalled representation of value. version indicates the file format.
The following functions allow marshalled values to be read back in.
XXX What about error detection? It appears that reading past the end of the file will always result in a negative numeric value (where that’s relevant), but it’s not clear that negative values won’t be handled properly when there’s no error. What’s the right way to tell? Should only non-negative values be written using these routines?
Return a C long from the data stream in a FILE* opened for reading. Only a 32-bit value can be read in using this function, regardless of the native size of long.
Return a C short from the data stream in a FILE* opened for reading. Only a 16-bit value can be read in using this function, regardless of the native size of short.
Return a Python object from the data stream in a FILE* opened for reading. On error, sets the appropriate exception (EOFError or TypeError) and returns NULL.
Return a Python object from the data stream in a FILE* opened for reading. Unlike PyMarshal_ReadObjectFromFile(), this function assumes that no further objects will be read from the file, allowing it to aggressively load file data into memory so that the de-serialization can operate from data in memory rather than reading a byte at a time from the file. Only use these variant if you are certain that you won’t be reading anything else from the file. On error, sets the appropriate exception (EOFError or TypeError) and returns NULL.
These functions are useful when creating your own extensions functions and methods. Additional information and examples are available in Extending and Embedding the Python Interpreter.
The first three of these functions described, PyArg_ParseTuple(), PyArg_ParseTupleAndKeywords(), and PyArg_Parse(), all use format strings which are used to tell the function about the expected arguments. The format strings use the same syntax for each of these functions.
A format string consists of zero or more “format units.” A format unit describes one Python object; it is usually a single character or a parenthesized sequence of format units. With a few exceptions, a format unit that is not a parenthesized sequence normally corresponds to a single address argument to these functions. In the following description, the quoted form is the format unit; the entry in (round) parentheses is the Python object type that matches the format unit; and the entry in [square] brackets is the type of the C variable(s) whose address should be passed.
Convert a Python string or Unicode object to a C pointer to a character string. You must not provide storage for the string itself; a pointer to an existing string is stored into the character pointer variable whose address you pass. The C string is NUL-terminated. The Python string must not contain embedded NUL bytes; if it does, a TypeError exception is raised. Unicode objects are converted to C strings using the default encoding. If this conversion fails, a UnicodeError is raised.
This variant on s stores into two C variables, the first one a pointer to a character string, the second one its length. In this case the Python string may contain embedded null bytes. Unicode objects pass back a pointer to the default encoded string version of the object if such a conversion is possible. All other read-buffer compatible objects pass back a reference to the raw internal data representation.
This variant on s convert a Python bytes object to a C pointer to a character string. The bytes object must not contain embedded NUL bytes; if it does, a TypeError exception is raised.
This variant on s# stores into two C variables, the first one a pointer to a character string, the second one its length. This only accepts bytes objects.
Like s, but the Python object may also be None, in which case the C pointer is set to NULL.
This is to s# as z is to s.
Convert a Python Unicode object to a C pointer to a NUL-terminated buffer of 16-bit Unicode (UTF-16) data. As with s, there is no need to provide storage for the Unicode data buffer; a pointer to the existing Unicode data is stored into the Py_UNICODE pointer variable whose address you pass.
This variant on u stores into two C variables, the first one a pointer to a Unicode data buffer, the second one its length. Non-Unicode objects are handled by interpreting their read-buffer pointer as pointer to a Py_UNICODE array.
Like s, but the Python object may also be None, in which case the C pointer is set to NULL.
This is to u# as Z is to u.
This variant on s is used for encoding Unicode and objects convertible to Unicode into a character buffer. It only works for encoded data without embedded NUL bytes.
This format requires two arguments. The first is only used as input, and must be a const char* which points to the name of an encoding as a NUL-terminated string, or NULL, in which case the default encoding is used. An exception is raised if the named encoding is not known to Python. The second argument must be a char**; the value of the pointer it references will be set to a buffer with the contents of the argument text. The text will be encoded in the encoding specified by the first argument.
PyArg_ParseTuple() will allocate a buffer of the needed size, copy the encoded data into this buffer and adjust *buffer to reference the newly allocated storage. The caller is responsible for calling PyMem_Free() to free the allocated buffer after use.
Same as es except that 8-bit string objects are passed through without recoding them. Instead, the implementation assumes that the string object uses the encoding passed in as parameter.
This variant on s# is used for encoding Unicode and objects convertible to Unicode into a character buffer. Unlike the es format, this variant allows input data which contains NUL characters.
It requires three arguments. The first is only used as input, and must be a const char* which points to the name of an encoding as a NUL-terminated string, or NULL, in which case the default encoding is used. An exception is raised if the named encoding is not known to Python. The second argument must be a char**; the value of the pointer it references will be set to a buffer with the contents of the argument text. The text will be encoded in the encoding specified by the first argument. The third argument must be a pointer to an integer; the referenced integer will be set to the number of bytes in the output buffer.
There are two modes of operation:
If *buffer points a NULL pointer, the function will allocate a buffer of the needed size, copy the encoded data into this buffer and set *buffer to reference the newly allocated storage. The caller is responsible for calling PyMem_Free() to free the allocated buffer after usage.
If *buffer points to a non-NULL pointer (an already allocated buffer), PyArg_ParseTuple() will use this location as the buffer and interpret the initial value of *buffer_length as the buffer size. It will then copy the encoded data into the buffer and NUL-terminate it. If the buffer is not large enough, a ValueError will be set.
In both cases, *buffer_length is set to the length of the encoded data without the trailing NUL byte.
Same as es# except that string objects are passed through without recoding them. Instead, the implementation assumes that the string object uses the encoding passed in as parameter.
Convert a Python integer to a tiny int, stored in a C char.
Convert a Python integer to a tiny int without overflow checking, stored in a C unsigned char.
Convert a Python integer to a C short int.
Convert a Python integer to a C unsigned short int, without overflow checking.
Convert a Python integer to a plain C int.
Convert a Python integer to a C unsigned int, without overflow checking.
Convert a Python integer to a C long int.
Convert a Python integer to a C unsigned long without overflow checking.
Convert a Python integer to a C long long. This format is only available on platforms that support long long (or _int64 on Windows).
Convert a Python integer to a C unsigned long long without overflow checking. This format is only available on platforms that support unsigned long long (or unsigned _int64 on Windows).
Convert a Python integer to a C Py_ssize_t.
Convert a Python character, represented as a string of length 1, to a C char.
Convert a Python floating point number to a C float.
Convert a Python floating point number to a C double.
Convert a Python complex number to a C Py_complex structure.
Store a Python object (without any conversion) in a C object pointer. The C program thus receives the actual object that was passed. The object’s reference count is not increased. The pointer stored is not NULL.
Store a Python object in a C object pointer. This is similar to O, but takes two C arguments: the first is the address of a Python type object, the second is the address of the C variable (of type PyObject*) into which the object pointer is stored. If the Python object does not have the required type, TypeError is raised.
Convert a Python object to a C variable through a converter function. This takes two arguments: the first is a function, the second is the address of a C variable (of arbitrary type), converted to void *. The converter function in turn is called as follows:
status = converter(object, address);
where object is the Python object to be converted and address is the void* argument that was passed to the PyArg_Parse*() function. The returned status should be 1 for a successful conversion and 0 if the conversion has failed. When the conversion fails, the converter function should raise an exception.
Like O but requires that the Python object is a string object. Raises TypeError if the object is not a string object. The C variable may also be declared as PyObject*.
Like O but requires that the Python object is a Unicode object. Raises TypeError if the object is not a Unicode object. The C variable may also be declared as PyObject*.
Like s#, but accepts any object which implements the read-only buffer interface. The char* variable is set to point to the first byte of the buffer, and the int is set to the length of the buffer. Only single-segment buffer objects are accepted; TypeError is raised for all others.
Similar to s, but accepts any object which implements the read-write buffer interface. The caller must determine the length of the buffer by other means, or use w# instead. Only single-segment buffer objects are accepted; TypeError is raised for all others.
Like s#, but accepts any object which implements the read-write buffer interface. The char * variable is set to point to the first byte of the buffer, and the int is set to the length of the buffer. Only single-segment buffer objects are accepted; TypeError is raised for all others.
The object must be a Python sequence whose length is the number of format units in items. The C arguments must correspond to the individual format units in items. Format units for sequences may be nested.
It is possible to pass “long” integers (integers whose value exceeds the platform’s LONG_MAX) however no proper range checking is done — the most significant bits are silently truncated when the receiving field is too small to receive the value (actually, the semantics are inherited from downcasts in C — your mileage may vary).
A few other characters have a meaning in a format string. These may not occur inside nested parentheses. They are:
Indicates that the remaining arguments in the Python argument list are optional. The C variables corresponding to optional arguments should be initialized to their default value — when an optional argument is not specified, PyArg_ParseTuple() does not touch the contents of the corresponding C variable(s).
The list of format units ends here; the string after the colon is used as the function name in error messages (the “associated value” of the exception that PyArg_ParseTuple() raises).
The list of format units ends here; the string after the semicolon is used as the error message instead of the default error message. Clearly, : and ; mutually exclude each other.
Note that any Python object references which are provided to the caller are borrowed references; do not decrement their reference count!
Additional arguments passed to these functions must be addresses of variables whose type is determined by the format string; these are used to store values from the input tuple. There are a few cases, as described in the list of format units above, where these parameters are used as input values; they should match what is specified for the corresponding format unit in that case.
For the conversion to succeed, the arg object must match the format and the format must be exhausted. On success, the PyArg_Parse*() functions return true, otherwise they return false and raise an appropriate exception.
Parse the parameters of a function that takes only positional parameters into local variables. Returns true on success; on failure, it returns false and raises the appropriate exception.
Identical to PyArg_ParseTuple(), except that it accepts a va_list rather than a variable number of arguments.
Parse the parameters of a function that takes both positional and keyword parameters into local variables. Returns true on success; on failure, it returns false and raises the appropriate exception.
Identical to PyArg_ParseTupleAndKeywords(), except that it accepts a va_list rather than a variable number of arguments.
Function used to deconstruct the argument lists of “old-style” functions — these are functions which use the METH_OLDARGS parameter parsing method. This is not recommended for use in parameter parsing in new code, and most code in the standard interpreter has been modified to no longer use this for that purpose. It does remain a convenient way to decompose other tuples, however, and may continue to be used for that purpose.
A simpler form of parameter retrieval which does not use a format string to specify the types of the arguments. Functions which use this method to retrieve their parameters should be declared as METH_VARARGS in function or method tables. The tuple containing the actual parameters should be passed as args; it must actually be a tuple. The length of the tuple must be at least min and no more than max; min and max may be equal. Additional arguments must be passed to the function, each of which should be a pointer to a PyObject* variable; these will be filled in with the values from args; they will contain borrowed references. The variables which correspond to optional parameters not given by args will not be filled in; these should be initialized by the caller. This function returns true on success and false if args is not a tuple or contains the wrong number of elements; an exception will be set if there was a failure.
This is an example of the use of this function, taken from the sources for the _weakref helper module for weak references:
static PyObject *
weakref_ref(PyObject *self, PyObject *args)
{
PyObject *object;
PyObject *callback = NULL;
PyObject *result = NULL;
.. cnid:: 75
if (PyArg_UnpackTuple(args, "ref", 1, 2, &object, &callback)) {
result = PyWeakref_NewRef(object, callback);
}
return result;
}
The call to PyArg_UnpackTuple() in this example is entirely equivalent to this call to PyArg_ParseTuple():
PyArg_ParseTuple(args, "O|O:ref", &object, &callback)
Create a new value based on a format string similar to those accepted by the PyArg_Parse*() family of functions and a sequence of values. Returns the value or NULL in the case of an error; an exception will be raised if NULL is returned.
Py_BuildValue() does not always build a tuple. It builds a tuple only if its format string contains two or more format units. If the format string is empty, it returns None; if it contains exactly one format unit, it returns whatever object is described by that format unit. To force it to return a tuple of size 0 or one, parenthesize the format string.
When memory buffers are passed as parameters to supply data to build objects, as for the s and s# formats, the required data is copied. Buffers provided by the caller are never referenced by the objects created by Py_BuildValue(). In other words, if your code invokes malloc() and passes the allocated memory to Py_BuildValue(), your code is responsible for calling free() for that memory once Py_BuildValue() returns.
In the following description, the quoted form is the format unit; the entry in (round) parentheses is the Python object type that the format unit will return; and the entry in [square] brackets is the type of the C value(s) to be passed.
The characters space, tab, colon and comma are ignored in format strings (but not within format units such as s#). This can be used to make long format strings a tad more readable.
Convert a null-terminated C string to a Python object. If the C string pointer is NULL, None is used.
Convert a C string and its length to a Python object. If the C string pointer is NULL, the length is ignored and None is returned.
Same as s.
Same as s#.
Convert a null-terminated buffer of Unicode (UCS-2 or UCS-4) data to a Python Unicode object. If the Unicode buffer pointer is NULL, None is returned.
Convert a Unicode (UCS-2 or UCS-4) data buffer and its length to a Python Unicode object. If the Unicode buffer pointer is NULL, the length is ignored and None is returned.
Convert a null-terminated C string to a Python unicode object. If the C string pointer is NULL, None is used.
Convert a C string and its length to a Python unicode object. If the C string pointer is NULL, the length is ignored and None is returned.
Convert a plain C int to a Python integer object.
Convert a plain C char to a Python integer object.
Convert a plain C short int to a Python integer object.
Convert a C long int to a Python integer object.
Convert a C unsigned char to a Python integer object.
Convert a C unsigned short int to a Python integer object.
Convert a C unsigned int to a Python long integer object.
Convert a C unsigned long to a Python long integer object.
Convert a C long long to a Python integer object. Only available on platforms that support long long.
Convert a C unsigned long long to a Python integer object. Only available on platforms that support unsigned long long.
Convert a C Py_ssize_t to a Python integer.
Convert a C int representing a character to a Python string of length 1.
Convert a C double to a Python floating point number.
Same as d.
Convert a C Py_complex structure to a Python complex number.
Pass a Python object untouched (except for its reference count, which is incremented by one). If the object passed in is a NULL pointer, it is assumed that this was caused because the call producing the argument found an error and set an exception. Therefore, Py_BuildValue() will return NULL but won’t raise an exception. If no exception has been raised yet, SystemError is set.
Same as O.
Same as O, except it doesn’t increment the reference count on the object. Useful when the object is created by a call to an object constructor in the argument list.
Convert anything to a Python object through a converter function. The function is called with anything (which should be compatible with void *) as its argument and should return a “new” Python object, or NULL if an error occurred.
Convert a sequence of C values to a Python tuple with the same number of items.
Convert a sequence of C values to a Python list with the same number of items.
Convert a sequence of C values to a Python dictionary. Each pair of consecutive C values adds one item to the dictionary, serving as key and value, respectively.
If there is an error in the format string, the SystemError exception is set and NULL returned.
Functions for number conversion and formatted string output.
Output not more than size bytes to str according to the format string format and the extra arguments. See the Unix man page snprintf(2).
Output not more than size bytes to str according to the format string format and the variable argument list va. Unix man page vsnprintf(2).
PyOS_snprintf() and PyOS_vsnprintf() wrap the Standard C library functions snprintf() and vsnprintf(). Their purpose is to guarantee consistent behavior in corner cases, which the Standard C functions do not.
The wrappers ensure that str*[*size-1] is always '\0' upon return. They never write more than size bytes (including the trailing '\0') into str. Both functions require that str != NULL, size > 0 and format != NULL.
If the platform doesn’t have vsnprintf() and the buffer size needed to avoid truncation exceeds size by more than 512 bytes, Python aborts with a Py_FatalError.
The return value (rv) for these functions should be interpreted as follows:
When 0 <= rv < size, the output conversion was successful and rv characters were written to str (excluding the trailing '\0' byte at str*[*rv]).
When rv >= size, the output conversion was truncated and a buffer with rv + 1 bytes would have been needed to succeed. str*[*size-1] is '\0' in this case.
When rv < 0, “something bad happened.” str*[*size-1] is '\0' in this case too, but the rest of str is undefined. The exact cause of the error depends on the underlying platform.
The following functions provide locale-independent string to number conversions.
Convert a string to a double. This function behaves like the Standard C function strtod() does in the C locale. It does this without changing the current locale, since that would not be thread-safe.
PyOS_ascii_strtod() should typically be used for reading configuration files or other non-user input that should be locale independent.
See the Unix man page strtod(2) for details.
Convert a double to a string using the '.' as the decimal separator. format is a printf()-style format string specifying the number format. Allowed conversion characters are 'e', 'E', 'f', 'F', 'g' and 'G'.
The return value is a pointer to buffer with the converted string or NULL if the conversion failed.
Convert a string to a double in a locale-independent way.
See the Unix man page atof(2) for details.
Return a dictionary of the builtins in the current execution frame, or the interpreter of the thread state if no frame is currently executing.
Return a dictionary of the local variables in the current execution frame, or NULL if no frame is currently executing.
Return a dictionary of the global variables in the current execution frame, or NULL if no frame is currently executing.
Return the current thread state’s frame, which is NULL if no frame is currently executing.
If there is a current frame and it is executing in restricted mode, return true, otherwise false.
Return the name of func if it is a function, class or instance object, else the name of funcs type.
Return a description string, depending on the type of func. Return values include “()” for functions and methods, ” constructor”, ” instance”, and ” object”. Concatenated with the result of PyEval_GetFuncName(), the result will be a description of func.
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