The functions described in this chapter will let you handle and raise Python
exceptions. It is important to understand some of the basics of Python
exception handling. It works somewhat like the POSIX errno variable:
there is a global indicator (per thread) of the last error that occurred. Most
C API functions don't clear this on success, but will set it to indicate the
cause of the error on failure. Most C API functions also return an error
indicator, usually NULL if they are supposed to return a pointer, or -1
if they return an integer (exception: the PyArg_*() functions
return 1 for success and 0 for failure).
Concretely, the error indicator consists of three object pointers: the exception's type, the exception's value, and the traceback object. Any of those pointers can be NULL if non-set (although some combinations are forbidden, for example you can't have a non-NULL traceback if the exception type is NULL).
When a function must fail because some function it called failed, it generally doesn't set the error indicator; the function it called already set it. It is responsible for either handling the error and clearing the exception or returning after cleaning up any resources it holds (such as object references or memory allocations); it should not continue normally if it is not prepared to handle the error. If returning due to an error, it is important to indicate to the caller that an error has been set. If the error is not handled or carefully propagated, additional calls into the Python/C API may not behave as intended and may fail in mysterious ways.
Note
The error indicator is not the result of sys.exc_info().
The former corresponds to an exception that is not yet caught (and is
therefore still propagating), while the latter returns an exception after
it is caught (and has therefore stopped propagating).
void PyErr_Clear()
Clear the error indicator. If the error indicator is not set, there is no effect.
void PyErr_PrintEx(int set_sys_last_vars)
Print a standard traceback to sys.stderr and clear the error indicator.
Call this function only when the error indicator is set. (Otherwise it will
cause a fatal error!)
If set_sys_last_vars is nonzero, the variables sys.last_type,
sys.last_value and sys.last_traceback will be set to the
type, value and traceback of the printed exception, respectively.
void PyErr_Print()
Alias for PyErr_PrintEx(1).
void PyErr_WriteUnraisable(PyObject *obj)
This utility function prints a warning message to sys.stderr when an
exception has been set but it is impossible for the interpreter to actually
raise the exception. It is used, for example, when an exception occurs in an
__del__() method.
The function is called with a single argument obj that identifies the context in which the unraisable exception occurred. If possible, the repr of obj will be printed in the warning message.
These functions help you set the current thread's error indicator.
For convenience, some of these functions will always return a
NULL pointer for use in a return statement.
void PyErr_SetString(PyObject *type, const char *message)
This is the most common way to set the error indicator. The first argument
specifies the exception type; it is normally one of the standard exceptions,
e.g. PyExc_RuntimeError. You need not increment its reference count.
The second argument is an error message; it is decoded from 'utf-8'.
void PyErr_SetObject(PyObject *type, PyObject *value)
This function is similar to PyErr_SetString() but lets you specify an
arbitrary Python object for the "value" of the exception.
PyObject* PyErr_Format(PyObject *exception, const char *format, ...)
Return value: Always NULL.This function sets the error indicator and returns NULL. exception
should be a Python exception class. The format and subsequent
parameters help format the error message; they have the same meaning and
values as in PyUnicode_FromFormat(). format is an ASCII-encoded
string.
PyObject* PyErr_FormatV(PyObject *exception, const char *format, va_list vargs)
Return value: Always NULL.Same as PyErr_Format(), but taking a va_list argument rather
than a variable number of arguments.
New in version 3.5.
void PyErr_SetNone(PyObject *type)
This is a shorthand for PyErr_SetObject(type, Py_None).
int PyErr_BadArgument()
This is a shorthand for PyErr_SetString(PyExc_TypeError, message), where
message indicates that a built-in operation was invoked with an illegal
argument. It is mostly for internal use.
PyObject* PyErr_NoMemory()
Return value: Always NULL.This is a shorthand for PyErr_SetNone(PyExc_MemoryError); it returns NULL
so an object allocation function can write return PyErr_NoMemory(); when it
runs out of memory.
PyObject* PyErr_SetFromErrno(PyObject *type)
Return value: Always NULL.This is a convenience function to raise an exception when a C library function
has returned an error and set the C variable errno. It constructs a
tuple object whose first item is the integer errno value and whose
second item is the corresponding error message (gotten from strerror()),
and then calls PyErr_SetObject(type, object). On Unix, when the
errno value is EINTR, indicating an interrupted system call,
this calls PyErr_CheckSignals(), and if that set the error indicator,
leaves it set to that. The function always returns NULL, so a wrapper
function around a system call can write return PyErr_SetFromErrno(type);
when the system call returns an error.
PyObject* PyErr_SetFromErrnoWithFilenameObject(PyObject *type, PyObject *filenameObject)
Similar to PyErr_SetFromErrno(), with the additional behavior that if
filenameObject is not NULL, it is passed to the constructor of type as
a third parameter. In the case of OSError exception,
this is used to define the filename attribute of the
exception instance.
PyObject* PyErr_SetFromErrnoWithFilenameObjects(PyObject *type, PyObject *filenameObject, PyObject *filenameObject2)
Similar to PyErr_SetFromErrnoWithFilenameObject(), but takes a second
filename object, for raising errors when a function that takes two filenames
fails.
New in version 3.4.
PyObject* PyErr_SetFromErrnoWithFilename(PyObject *type, const char *filename)
Return value: Always NULL.Similar to PyErr_SetFromErrnoWithFilenameObject(), but the filename
is given as a C string. filename is decoded from the filesystem encoding
(os.fsdecode()).
PyObject* PyErr_SetFromWindowsErr(int ierr)
Return value: Always NULL.This is a convenience function to raise WindowsError. If called with
ierr of 0, the error code returned by a call to GetLastError()
is used instead. It calls the Win32 function FormatMessage() to retrieve
the Windows description of error code given by ierr or GetLastError(),
then it constructs a tuple object whose first item is the ierr value and whose
second item is the corresponding error message (gotten from
FormatMessage()), and then calls PyErr_SetObject(PyExc_WindowsError,
object). This function always returns NULL. Availability: Windows.
PyObject* PyErr_SetExcFromWindowsErr(PyObject *type, int ierr)
Return value: Always NULL.Similar to PyErr_SetFromWindowsErr(), with an additional parameter
specifying the exception type to be raised. Availability: Windows.
PyObject* PyErr_SetFromWindowsErrWithFilename(int ierr, const char *filename)
Return value: Always NULL.Similar to PyErr_SetFromWindowsErrWithFilenameObject(), but the
filename is given as a C string. filename is decoded from the filesystem
encoding (os.fsdecode()). Availability: Windows.
PyObject* PyErr_SetExcFromWindowsErrWithFilenameObject(PyObject *type, int ierr, PyObject *filename)
Similar to PyErr_SetFromWindowsErrWithFilenameObject(), with an
additional parameter specifying the exception type to be raised.
Availability: Windows.
PyObject* PyErr_SetExcFromWindowsErrWithFilenameObjects(PyObject *type, int ierr, PyObject *filename, PyObject *filename2)
Similar to PyErr_SetExcFromWindowsErrWithFilenameObject(),
but accepts a second filename object.
Availability: Windows.
New in version 3.4.
PyObject* PyErr_SetExcFromWindowsErrWithFilename(PyObject *type, int ierr, const char *filename)
Return value: Always NULL.Similar to PyErr_SetFromWindowsErrWithFilename(), with an additional
parameter specifying the exception type to be raised. Availability: Windows.
PyObject* PyErr_SetImportError(PyObject *msg, PyObject *name, PyObject *path)
This is a convenience function to raise ImportError. msg will be
set as the exception's message string. name and path, both of which can
be NULL, will be set as the ImportError's respective name
and path attributes.
New in version 3.3.
void PyErr_SyntaxLocationObject(PyObject *filename, int lineno, int col_offset)
Set file, line, and offset information for the current exception. If the
current exception is not a SyntaxError, then it sets additional
attributes, which make the exception printing subsystem think the exception
is a SyntaxError.
New in version 3.4.
void PyErr_SyntaxLocationEx(const char *filename, int lineno, int col_offset)
Like PyErr_SyntaxLocationObject(), but filename is a byte string
decoded from the filesystem encoding (os.fsdecode()).
New in version 3.2.
void PyErr_SyntaxLocation(const char *filename, int lineno)
Like PyErr_SyntaxLocationEx(), but the col_offset parameter is
omitted.
void PyErr_BadInternalCall()
This is a shorthand for PyErr_SetString(PyExc_SystemError, message),
where message indicates that an internal operation (e.g. a Python/C API
function) was invoked with an illegal argument. It is mostly for internal
use.
Use these functions to issue warnings from C code. They mirror similar
functions exported by the Python warnings module. They normally
print a warning message to sys.stderr; however, it is
also possible that the user has specified that warnings are to be turned into
errors, and in that case they will raise an exception. It is also possible that
the functions raise an exception because of a problem with the warning machinery.
The return value is 0 if no exception is raised, or -1 if an exception
is raised. (It is not possible to determine whether a warning message is
actually printed, nor what the reason is for the exception; this is
intentional.) If an exception is raised, the caller should do its normal
exception handling (for example, Py_DECREF() owned references and return
an error value).
int PyErr_WarnEx(PyObject *category, const char *message, Py_ssize_t stack_level)
Issue a warning message. The category argument is a warning category (see
below) or NULL; the message argument is a UTF-8 encoded string. stack_level is a
positive number giving a number of stack frames; the warning will be issued from
the currently executing line of code in that stack frame. A stack_level of 1
is the function calling PyErr_WarnEx(), 2 is the function above that,
and so forth.
Warning categories must be subclasses of PyExc_Warning;
PyExc_Warning is a subclass of PyExc_Exception;
the default warning category is PyExc_RuntimeWarning. The standard
Python warning categories are available as global variables whose names are
enumerated at Standard Warning Categories.
For information about warning control, see the documentation for the
warnings module and the -W option in the command line
documentation. There is no C API for warning control.
PyObject* PyErr_SetImportErrorSubclass(PyObject *msg, PyObject *name, PyObject *path)
Much like PyErr_SetImportError() but this function allows for
specifying a subclass of ImportError to raise.
New in version 3.6.
int PyErr_WarnExplicitObject(PyObject *category, PyObject *message, PyObject *filename, int lineno, PyObject *module, PyObject *registry)
Issue a warning message with explicit control over all warning attributes. This
is a straightforward wrapper around the Python function
warnings.warn_explicit(), see there for more information. The module
and registry arguments may be set to NULL to get the default effect
described there.
New in version 3.4.
int PyErr_WarnExplicit(PyObject *category, const char *message, const char *filename, int lineno, const char *module, PyObject *registry)
Similar to PyErr_WarnExplicitObject() except that message and
module are UTF-8 encoded strings, and filename is decoded from the
filesystem encoding (os.fsdecode()).
int PyErr_WarnFormat(PyObject *category, Py_ssize_t stack_level, const char *format, ...)
Function similar to PyErr_WarnEx(), but use
PyUnicode_FromFormat() to format the warning message. format is
an ASCII-encoded string.
New in version 3.2.
int PyErr_ResourceWarning(PyObject *source, Py_ssize_t stack_level, const char *format, ...)
Function similar to PyErr_WarnFormat(), but category is
ResourceWarning and pass source to warnings.WarningMessage().
New in version 3.6.
PyObject* PyErr_Occurred()
Return value: Borrowed reference.Test whether the error indicator is set. If set, return the exception type
(the first argument to the last call to one of the PyErr_Set*()
functions or to PyErr_Restore()). If not set, return NULL. You do not
own a reference to the return value, so you do not need to Py_DECREF()
it.
Note
Do not compare the return value to a specific exception; use
PyErr_ExceptionMatches() instead, shown below. (The comparison could
easily fail since the exception may be an instance instead of a class, in the
case of a class exception, or it may be a subclass of the expected exception.)
int PyErr_ExceptionMatches(PyObject *exc)
Equivalent to PyErr_GivenExceptionMatches(PyErr_Occurred(), exc). This
should only be called when an exception is actually set; a memory access
violation will occur if no exception has been raised.
int PyErr_GivenExceptionMatches(PyObject *given, PyObject *exc)
Return true if the given exception matches the exception type in exc. If exc is a class object, this also returns true when given is an instance of a subclass. If exc is a tuple, all exception types in the tuple (and recursively in subtuples) are searched for a match.
void PyErr_Fetch(PyObject **ptype, PyObject **pvalue, PyObject **ptraceback)
Retrieve the error indicator into three variables whose addresses are passed. If the error indicator is not set, set all three variables to NULL. If it is set, it will be cleared and you own a reference to each object retrieved. The value and traceback object may be NULL even when the type object is not.
Note
This function is normally only used by code that needs to catch exceptions or by code that needs to save and restore the error indicator temporarily, e.g.:
{
PyObject *type, *value, *traceback;
PyErr_Fetch(&type, &value, &traceback);
/* ... code that might produce other errors ... */
PyErr_Restore(type, value, traceback);
}
void PyErr_Restore(PyObject *type, PyObject *value, PyObject *traceback)
Set the error indicator from the three objects. If the error indicator is already set, it is cleared first. If the objects are NULL, the error indicator is cleared. Do not pass a NULL type and non-NULL value or traceback. The exception type should be a class. Do not pass an invalid exception type or value. (Violating these rules will cause subtle problems later.) This call takes away a reference to each object: you must own a reference to each object before the call and after the call you no longer own these references. (If you don't understand this, don't use this function. I warned you.)
Note
This function is normally only used by code that needs to save and restore the
error indicator temporarily. Use PyErr_Fetch() to save the current
error indicator.
void PyErr_NormalizeException(PyObject**exc, PyObject**val, PyObject**tb)
Under certain circumstances, the values returned by PyErr_Fetch() below
can be "unnormalized", meaning that *exc is a class object but *val is
not an instance of the same class. This function can be used to instantiate
the class in that case. If the values are already normalized, nothing happens.
The delayed normalization is implemented to improve performance.
Note
This function does not implicitly set the __traceback__
attribute on the exception value. If setting the traceback
appropriately is desired, the following additional snippet is needed:
if (tb != NULL) {
PyException_SetTraceback(val, tb);
}
void PyErr_GetExcInfo(PyObject **ptype, PyObject **pvalue, PyObject **ptraceback)
Retrieve the exception info, as known from sys.exc_info(). This refers
to an exception that was already caught, not to an exception that was
freshly raised. Returns new references for the three objects, any of which
may be NULL. Does not modify the exception info state.
Note
This function is not normally used by code that wants to handle exceptions.
Rather, it can be used when code needs to save and restore the exception
state temporarily. Use PyErr_SetExcInfo() to restore or clear the
exception state.
New in version 3.3.
void PyErr_SetExcInfo(PyObject *type, PyObject *value, PyObject *traceback)
Set the exception info, as known from sys.exc_info(). This refers
to an exception that was already caught, not to an exception that was
freshly raised. This function steals the references of the arguments.
To clear the exception state, pass NULL for all three arguments.
For general rules about the three arguments, see PyErr_Restore().
Note
This function is not normally used by code that wants to handle exceptions.
Rather, it can be used when code needs to save and restore the exception
state temporarily. Use PyErr_GetExcInfo() to read the exception
state.
New in version 3.3.
int PyErr_CheckSignals()
This function interacts with Python's signal handling. It checks whether a
signal has been sent to the processes and if so, invokes the corresponding
signal handler. If the signal module is supported, this can invoke a
signal handler written in Python. In all cases, the default effect for
SIGINT is to raise the KeyboardInterrupt exception. If an
exception is raised the error indicator is set and the function returns -1;
otherwise the function returns 0. The error indicator may or may not be
cleared if it was previously set.
void PyErr_SetInterrupt()
This function simulates the effect of a SIGINT signal arriving --- the
next time PyErr_CheckSignals() is called, KeyboardInterrupt will
be raised. It may be called without holding the interpreter lock.
int PySignal_SetWakeupFd(int fd)
This utility function specifies a file descriptor to which the signal number is written as a single byte whenever a signal is received. fd must be non-blocking. It returns the previous such file descriptor.
The value -1 disables the feature; this is the initial state.
This is equivalent to signal.set_wakeup_fd() in Python, but without any
error checking. fd should be a valid file descriptor. The function should
only be called from the main thread.
Changed in version 3.5: On Windows, the function now also supports socket handles.
PyObject* PyErr_NewException(const char *name, PyObject *base, PyObject *dict)
Return value: New reference.This utility function creates and returns a new exception class. The name
argument must be the name of the new exception, a C string of the form
module.classname. The base and dict arguments are normally NULL.
This creates a class object derived from Exception (accessible in C as
PyExc_Exception).
The __module__ attribute of the new class is set to the first part (up
to the last dot) of the name argument, and the class name is set to the last
part (after the last dot). The base argument can be used to specify alternate
base classes; it can either be only one class or a tuple of classes. The dict
argument can be used to specify a dictionary of class variables and methods.
PyObject* PyErr_NewExceptionWithDoc(const char *name, const char *doc, PyObject *base, PyObject *dict)
Return value: New reference.Same as PyErr_NewException(), except that the new exception class can
easily be given a docstring: If doc is non-NULL, it will be used as the
docstring for the exception class.
New in version 3.2.
PyObject* PyException_GetTraceback(PyObject *ex)
Return value: New reference.Return the traceback associated with the exception as a new reference, as
accessible from Python through __traceback__. If there is no
traceback associated, this returns NULL.
int PyException_SetTraceback(PyObject *ex, PyObject *tb)
Set the traceback associated with the exception to tb. Use Py_None to
clear it.
PyObject* PyException_GetContext(PyObject *ex)
Return the context (another exception instance during whose handling ex was
raised) associated with the exception as a new reference, as accessible from
Python through __context__. If there is no context associated, this
returns NULL.
void PyException_SetContext(PyObject *ex, PyObject *ctx)
Set the context associated with the exception to ctx. Use NULL to clear it. There is no type check to make sure that ctx is an exception instance. This steals a reference to ctx.
PyObject* PyException_GetCause(PyObject *ex)
Return the cause (either an exception instance, or None,
set by raise ... from ...) associated with the exception as a new
reference, as accessible from Python through __cause__.
void PyException_SetCause(PyObject *ex, PyObject *cause)
Set the cause associated with the exception to cause. Use NULL to clear
it. There is no type check to make sure that cause is either an exception
instance or None. This steals a reference to cause.
__suppress_context__ is implicitly set to True by this function.
The following functions are used to create and modify Unicode exceptions from C.
PyObject* PyUnicodeDecodeError_Create(const char *encoding, const char *object, Py_ssize_t length, Py_ssize_t start, Py_ssize_t end, const char *reason)
Create a UnicodeDecodeError object with the attributes encoding,
object, length, start, end and reason. encoding and reason are
UTF-8 encoded strings.
PyObject* PyUnicodeEncodeError_Create(const char *encoding, const Py_UNICODE *object, Py_ssize_t length, Py_ssize_t start, Py_ssize_t end, const char *reason)
Create a UnicodeEncodeError object with the attributes encoding,
object, length, start, end and reason. encoding and reason are
UTF-8 encoded strings.
PyObject* PyUnicodeTranslateError_Create(const Py_UNICODE *object, Py_ssize_t length, Py_ssize_t start, Py_ssize_t end, const char *reason)
Create a UnicodeTranslateError object with the attributes object,
length, start, end and reason. reason is a UTF-8 encoded string.
PyObject* PyUnicodeDecodeError_GetEncoding(PyObject *exc)
PyObject* PyUnicodeEncodeError_GetEncoding(PyObject *exc)
Return the encoding attribute of the given exception object.
PyObject* PyUnicodeDecodeError_GetObject(PyObject *exc)
PyObject* PyUnicodeEncodeError_GetObject(PyObject *exc)
PyObject* PyUnicodeTranslateError_GetObject(PyObject *exc)
Return the object attribute of the given exception object.
int PyUnicodeDecodeError_GetStart(PyObject *exc, Py_ssize_t *start)
int PyUnicodeEncodeError_GetStart(PyObject *exc, Py_ssize_t *start)
int PyUnicodeTranslateError_GetStart(PyObject *exc, Py_ssize_t *start)
Get the start attribute of the given exception object and place it into
*start. start must not be NULL. Return 0 on success, -1 on
failure.
int PyUnicodeDecodeError_SetStart(PyObject *exc, Py_ssize_t start)
int PyUnicodeEncodeError_SetStart(PyObject *exc, Py_ssize_t start)
int PyUnicodeTranslateError_SetStart(PyObject *exc, Py_ssize_t start)
Set the start attribute of the given exception object to start. Return
0 on success, -1 on failure.
int PyUnicodeDecodeError_GetEnd(PyObject *exc, Py_ssize_t *end)
int PyUnicodeEncodeError_GetEnd(PyObject *exc, Py_ssize_t *end)
int PyUnicodeTranslateError_GetEnd(PyObject *exc, Py_ssize_t *end)
Get the end attribute of the given exception object and place it into
*end. end must not be NULL. Return 0 on success, -1 on
failure.
int PyUnicodeDecodeError_SetEnd(PyObject *exc, Py_ssize_t end)
int PyUnicodeEncodeError_SetEnd(PyObject *exc, Py_ssize_t end)
int PyUnicodeTranslateError_SetEnd(PyObject *exc, Py_ssize_t end)
Set the end attribute of the given exception object to end. Return 0
on success, -1 on failure.
PyObject* PyUnicodeDecodeError_GetReason(PyObject *exc)
PyObject* PyUnicodeEncodeError_GetReason(PyObject *exc)
PyObject* PyUnicodeTranslateError_GetReason(PyObject *exc)
Return the reason attribute of the given exception object.
int PyUnicodeDecodeError_SetReason(PyObject *exc, const char *reason)
int PyUnicodeEncodeError_SetReason(PyObject *exc, const char *reason)
int PyUnicodeTranslateError_SetReason(PyObject *exc, const char *reason)
Set the reason attribute of the given exception object to reason. Return
0 on success, -1 on failure.
These two functions provide a way to perform safe recursive calls at the C level, both in the core and in extension modules. They are needed if the recursive code does not necessarily invoke Python code (which tracks its recursion depth automatically).
int Py_EnterRecursiveCall(const char *where)
Marks a point where a recursive C-level call is about to be performed.
If USE_STACKCHECK is defined, this function checks if the OS
stack overflowed using PyOS_CheckStack(). In this is the case, it
sets a MemoryError and returns a nonzero value.
The function then checks if the recursion limit is reached. If this is the
case, a RecursionError is set and a nonzero value is returned.
Otherwise, zero is returned.
where should be a string such as " in instance check" to be
concatenated to the RecursionError message caused by the recursion
depth limit.
void Py_LeaveRecursiveCall()
Ends a Py_EnterRecursiveCall(). Must be called once for each
successful invocation of Py_EnterRecursiveCall().
Properly implementing tp_repr for container types requires
special recursion handling. In addition to protecting the stack,
tp_repr also needs to track objects to prevent cycles. The
following two functions facilitate this functionality. Effectively,
these are the C equivalent to reprlib.recursive_repr().
int Py_ReprEnter(PyObject *object)
Called at the beginning of the tp_repr implementation to
detect cycles.
If the object has already been processed, the function returns a
positive integer. In that case the tp_repr implementation
should return a string object indicating a cycle. As examples,
dict objects return {...} and list objects
return [...].
The function will return a negative integer if the recursion limit
is reached. In that case the tp_repr implementation should
typically return NULL.
Otherwise, the function returns zero and the tp_repr
implementation can continue normally.
void Py_ReprLeave(PyObject *object)
Ends a Py_ReprEnter(). Must be called once for each
invocation of Py_ReprEnter() that returns zero.
All standard Python exceptions are available as global variables whose names are
PyExc_ followed by the Python exception name. These have the type
PyObject*; they are all class objects. For completeness, here are all
the variables:
| C Name | Python Name | Notes |
|---|---|---|
PyExc_BaseException | BaseException | (1) |
PyExc_Exception | Exception | (1) |
PyExc_ArithmeticError | ArithmeticError | (1) |
PyExc_AssertionError | AssertionError | |
PyExc_AttributeError | AttributeError | |
PyExc_BlockingIOError | BlockingIOError | |
PyExc_BrokenPipeError | BrokenPipeError | |
PyExc_BufferError | BufferError | |
PyExc_ChildProcessError | ChildProcessError | |
PyExc_ConnectionAbortedError | ConnectionAbortedError | |
PyExc_ConnectionError | ConnectionError | |
PyExc_ConnectionRefusedError | ConnectionRefusedError | |
PyExc_ConnectionResetError | ConnectionResetError | |
PyExc_EOFError | EOFError | |
PyExc_FileExistsError | FileExistsError | |
PyExc_FileNotFoundError | FileNotFoundError | |
PyExc_FloatingPointError | FloatingPointError | |
PyExc_GeneratorExit | GeneratorExit | |
PyExc_ImportError | ImportError | |
PyExc_IndentationError | IndentationError | |
PyExc_IndexError | IndexError | |
PyExc_InterruptedError | InterruptedError | |
PyExc_IsADirectoryError | IsADirectoryError | |
PyExc_KeyError | KeyError | |
PyExc_KeyboardInterrupt | KeyboardInterrupt | |
PyExc_LookupError | LookupError | (1) |
PyExc_MemoryError | MemoryError | |
PyExc_ModuleNotFoundError | ModuleNotFoundError | |
PyExc_NameError | NameError | |
PyExc_NotADirectoryError | NotADirectoryError | |
PyExc_NotImplementedError | NotImplementedError | |
PyExc_OSError | OSError | (1) |
PyExc_OverflowError | OverflowError | |
PyExc_PermissionError | PermissionError | |
PyExc_ProcessLookupError | ProcessLookupError | |
PyExc_RecursionError | RecursionError | |
PyExc_ReferenceError | ReferenceError | (2) |
PyExc_RuntimeError | RuntimeError | |
PyExc_StopAsyncIteration | StopAsyncIteration | |
PyExc_StopIteration | StopIteration | |
PyExc_SyntaxError | SyntaxError | |
PyExc_SystemError | SystemError | |
PyExc_SystemExit | SystemExit | |
PyExc_TabError | TabError | |
PyExc_TimeoutError | TimeoutError | |
PyExc_TypeError | TypeError | |
PyExc_UnboundLocalError | UnboundLocalError | |
PyExc_UnicodeDecodeError | UnicodeDecodeError | |
PyExc_UnicodeEncodeError | UnicodeEncodeError | |
PyExc_UnicodeError | UnicodeError | |
PyExc_UnicodeTranslateError | UnicodeTranslateError | |
PyExc_ValueError | ValueError | |
PyExc_ZeroDivisionError | ZeroDivisionError |
New in version 3.3: PyExc_BlockingIOError, PyExc_BrokenPipeError,
PyExc_ChildProcessError, PyExc_ConnectionError,
PyExc_ConnectionAbortedError, PyExc_ConnectionRefusedError,
PyExc_ConnectionResetError, PyExc_FileExistsError,
PyExc_FileNotFoundError, PyExc_InterruptedError,
PyExc_IsADirectoryError, PyExc_NotADirectoryError,
PyExc_PermissionError, PyExc_ProcessLookupError
and PyExc_TimeoutError were introduced following PEP 3151.
New in version 3.5: PyExc_StopAsyncIteration and PyExc_RecursionError.
New in version 3.6: PyExc_ModuleNotFoundError.
These are compatibility aliases to PyExc_OSError:
| C Name | Notes |
|---|---|
PyExc_EnvironmentError | |
PyExc_IOError | |
PyExc_WindowsError | (3) |
Changed in version 3.3: These aliases used to be separate exception types.
Notes:
- This is a base class for other standard exceptions.
- This is the same as
weakref.ReferenceError. - Only defined on Windows; protect code that uses this by testing that the
preprocessor macro
MS_WINDOWSis defined.
All standard Python warning categories are available as global variables whose
names are PyExc_ followed by the Python exception name. These have the type
PyObject*; they are all class objects. For completeness, here are all
the variables:
| C Name | Python Name | Notes |
|---|---|---|
PyExc_Warning | Warning | (1) |
PyExc_BytesWarning | BytesWarning | |
PyExc_DeprecationWarning | DeprecationWarning | |
PyExc_FutureWarning | FutureWarning | |
PyExc_ImportWarning | ImportWarning | |
PyExc_PendingDeprecationWarning | PendingDeprecationWarning | |
PyExc_ResourceWarning | ResourceWarning | |
PyExc_RuntimeWarning | RuntimeWarning | |
PyExc_SyntaxWarning | SyntaxWarning | |
PyExc_UnicodeWarning | UnicodeWarning | |
PyExc_UserWarning | UserWarning |
New in version 3.2: PyExc_ResourceWarning.
Notes:
- This is a base class for other standard warning categories.